Disulfide bond stabilized polypeptide compositions and methods of use

ABSTRACT

Provided herein are polypeptides comprising one or more non-native cysteine residues that form a disulfide bridge between non-native cysteines within the protein or between non-native cysteines of two monomers of the protein. Such modified human polypeptides are useful in treatment of genetic diseases via enzyme replacement therapy and/or gene therapy.

CROSS-REFERENCE

This application is a divisional of U.S. Ser. No. 16/598,960, filed onOct. 10, 2019, which claims the benefit of U.S. Provisional ApplicationNo. 62/744,069, filed Oct. 10, 2018, which application is herebyincorporated herein by reference in its entirety.

BACKGROUND

Genetic diseases can be treated with enzyme replacement therapy usingrecombinant polypeptides or gene therapy using nucleic acids encodingrecombinant proteins. For example, Fabry disease may be treated usingrecombinant alpha-galactosidase A or small molecule chaperones such as1-deoxygalactonojirimycin (Migalastat). However, the recombinantwildtype polypeptides often have poor stability at neutral pH and arequickly degraded in serum. This limits the half-life of the therapeuticenzyme substantially, as it is delivered by intravenous infusion.

SUMMARY

In certain aspects, there are provided gene therapy vectors comprising anucleic acid construct comprising: a nucleic acid encoding a stabilizedform of a protein for treating a genetic disorder. In some embodiments,the stabilized form comprises one or more non-native cysteine residuesthat form a disulfide bridge between non-native cysteines within theprotein or between non-native cysteines of two monomers of the protein.In some embodiments, the protein is selected from the group consistingof alpha-galactosidase A, β-glucocerebrosidase, glucocerebrosidase,lysosomal acid lipase, glycosaminoglycan alpha-L-iduronidase,alpha-L-iduronidase, N-sulfoglucosamine sulfohydrolase (SGSH),N-acetyl-alpha-glucosaminidase (NAGLU), iduronate-2-sulfatase,N-acetylgalactosamine-6-sulfatase, glycosaminoglycanN-acetylgalactosamine 4-sulfatase, alpha-glucosidase, tripeptidylpeptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs), ceroidlipofuscinoses neuronal 1, ceroid lipofuscinoses neuronal 2, ceroidlipofuscinoses neuronal 3, ceroid lipofuscinoses neuronal 4, ceroidlipofuscinoses neuronal 5, ceroid lipofuscinoses neuronal 6, ceroidlipofuscinoses neuronal 7, ceroid lipofuscinoses neuronal 8, ceroidlipofuscinoses neuronal 9, ceroid lipofuscinoses neuronal 10, ceroidlipofuscinoses neuronal 11, ceroid lipofuscinoses neuronal 12, ceroidlipofuscinoses neuronal 13, ceroid lipofuscinoses neuronal 14, ceroidlipofuscinoses neuronal 15, ceroid lipofuscinoses neuronal 16, andcyclin dependent kinase like 5. In some embodiments, the protein isselected from the group consisting of alpha-galactosidase A,β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase,glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase,N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase(NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase,glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase,tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs),ceroid lipofuscinoses neuronal 4, ceroid lipofuscinoses neuronal 10(cathepsin D), ceroid lipofuscinoses neuronal 11 (progranulin), ceroidlipofuscinoses neuronal 13 (cathepsin F), ceroid lipofuscinoses neuronal14 (KCTD7), ceroid lipofuscinoses neuronal 15 (TBCK), and cyclindependent kinase like 5. In some embodiments, the stabilized proteincomprises a lysosomal enzyme. In some embodiments, the stabilizedprotein comprises a stabilized α-galactosidase (α-GAL) protein. In someembodiments, the stabilized α-galactosidase A (α-GAL) protein comprisesone or more non-native cysteine residues selected from the groupconsisting of: (i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the stabilized protein comprises a stabilized palmitoylprotein thioesterase 1 (PPT1). In some embodiments, the stabilized PPT1protein comprises non-native cysteine residues A171C and A183C. In someembodiments, the stabilized protein has a longer half-life at pH 7.4compared to a corresponding protein without the non-native cysteines. Insome embodiments, the stabilized protein can replace a protein defectiveor deficient in the genetic disorder. In some embodiments, thestabilized protein can reduce or slow one or more symptoms associatedwith the genetic disorder. In some embodiments, the stabilized proteinis more effective at reducing or slowing one or more symptoms of thegenetic disorder, compared to an unstabilized protein. In someembodiments, the genetic disorder is a neurological disorder. In someembodiments, the genetic disorder is a lysosomal storage disorder. Insome embodiments, the genetic disorder is selected from the groupconsisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabrydisease, Gaucher disease type I, Gaucher disease type II, Gaucherdisease type III, Pompe disease, Tay Sachs disease, Sandhoff disease,metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis typeII, mucolipidosis type III, mucolipidosis type IV, Hurler disease,Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B,Sanfilippo disease type C, Sanfilippo disease type D, Morquio diseasetype A, Morquio disease type B, Maroteau-Lamy disease, Sly disease,Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pickdisease type C1, Niemann-Pick disease type C2, Schindler disease type I,Schindler disease type II, adenosine deaminase severe combinedimmunodeficiency (ADA-SCID), chronic granulomatous disease (CGD),infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis,and CDKL5 deficiency disease. In some embodiments, the gene therapyvector is a viral vector selected from the group consisting of anadenovirus vector, an adeno-associated virus vector, a retrovirusvector, a lentivirus vector, and a herpes virus vector. In someembodiments, the adeno-associated virus is a serotype selected from thegroup consisting of: AAV-1, AAV-2, AAV-3, AAV-4, AAV-5, AAV-6, AAV-7,AAV-8, AAV-9, AAV-10, AAV-11, AAV-12, AAV-13, AAV rh.74, AAV-B1 andAAV-hu68. In some embodiments, the nucleic acid construct is comprisedin a viral vector genome. In some embodiments, the viral vector genomecomprises a recombinant AAV (rAAV) genome. In some embodiments, the rAAVgenome comprises a self-complementary genome. In some embodiments, therAAV genome comprises a single-stranded genome. In some embodiments, therAAV genome comprises a first inverted terminal repeat and a secondinverted terminal repeat. In some embodiments, the AAV inverted terminalrepeats are AAV2 inverted terminal repeats. In some embodiments, therAAV genome further comprises an SV40 intron. In some embodiments, therAAV genome further comprises a poly-adenylation sequence. In someembodiments, the construct further comprises a nucleic acid sequenceencoding an α-GAL protein, wherein the nucleic acid sequence is at least85% identical to one of SEQ ID NOs: 7-12. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding an α-GALprotein, wherein the α-GAL protein comprises a sequence at least 85%identical to one of SEQ ID NOs: 1-6. In some embodiments, the constructfurther comprises a nucleic acid sequence encoding an α-GAL protein,wherein the nucleic acid sequence comprises the sequence of one of SEQID NOs: 8-12. In some embodiments, the construct further comprises anucleic acid sequence encoding an α-GAL protein, wherein the α-GALprotein comprises the sequence of one of SEQ ID NOs: 2-6. In someembodiments, the construct further comprises a nucleic acid sequenceencoding a PPT1 protein, wherein the nucleic acid sequence is at least85% identical to one of SEQ ID NOs: 15-16. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding a PPT1protein, wherein the PPT1 protein comprises a sequence at least 85%identical to one of SEQ ID NOs: 13-14. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding a PPT1protein, wherein the nucleic acid sequence comprises the sequence of SEQID NO: 16. In some embodiments, the construct further comprises anucleic acid sequence encoding a PPT1 protein, wherein the PPT1 proteincomprises the sequence of SEQ ID NO: 14. In some embodiments, theconstruct further comprises a promoter sequence. In some embodiments,the promoter is a constitutive promoter. In some embodiments, thepromoter is a tissue-specific promoter. In some embodiments, theconstruct further comprises one or more nucleic acid sequences selectedfrom the group consisting of: a Kozak sequence, a CrPV IRES, a nucleicacid sequence encoding a linker, a nucleic acid sequence encoding asignal sequence, and a nucleic acid sequence encoding an IGF2 peptide.In some embodiments, the signal peptide sequence comprises a bindingimmunoglobulin protein (Bip) signal sequence. In some embodiments, thesignal peptide sequence comprises the Bip signal sequence comprises anamino acid sequence at least 90% identical to an amino acid sequenceselected from the group consisting of SEQ ID NOs: 29-33. In someembodiments, the construct further comprises an internal ribosomal entrysequence (IRES). In some embodiments, the IRES comprises a cricketparalysis virus (CrPV) IRES. In some embodiments, the construct furthercomprises a nucleic acid sequence encoding a variant IGF2 (vIGF2)peptide. In some embodiments, the vIGF2 peptide comprising an amino acidsequence at least 90% identical to an amino acid sequence selected fromthe group consisting of SEQ ID NOs: 17-27. In some embodiments, thenucleic acid sequence encoding the vIGF2 peptide is 5′ to the nucleicacid sequence encoding the stabilized form of the protein. In someembodiments, the nucleic acid sequence encoding the vIGF2 peptide is 3′to the nucleic acid sequence encoding the stabilized form of theprotein. In some embodiments, the construct is packaged within a viralcapsid.

In additional aspects, there are provided pharmaceutical compositionscomprising a gene therapy vector comprising a nucleic acid constructcomprising: a nucleic acid encoding a stabilized form of a protein fortreating a genetic disorder and a pharmaceutically acceptable excipient,carrier, or diluent. In some embodiments, the stabilized form comprisesone or more non-native cysteine residues that form a disulfide bridgebetween non-native cysteines within the protein or between non-nativecysteines of two monomers of the protein. In some embodiments, theprotein is selected from the group consisting of alpha-galactosidase A,β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase,glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase,N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase(NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase,glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase,tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs),ceroid lipofuscinoses neuronal 1, ceroid lipofuscinoses neuronal 2,ceroid lipofuscinoses neuronal 3, ceroid lipofuscinoses neuronal 4,ceroid lipofuscinoses neuronal 5, ceroid lipofuscinoses neuronal 6,ceroid lipofuscinoses neuronal 7, ceroid lipofuscinoses neuronal 8,ceroid lipofuscinoses neuronal 9, ceroid lipofuscinoses neuronal 10,ceroid lipofuscinoses neuronal 11, ceroid lipofuscinoses neuronal 12,ceroid lipofuscinoses neuronal 13, ceroid lipofuscinoses neuronal 14,ceroid lipofuscinoses neuronal 15, ceroid lipofuscinoses neuronal 16,and cyclin dependent kinase like 5. In some embodiments, the protein isselected from the group consisting of alpha-galactosidase A,β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase,glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase,N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase(NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase,glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase,tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs),ceroid lipofuscinoses neuronal 4, ceroid lipofuscinoses neuronal 10(cathepsin D), ceroid lipofuscinoses neuronal 11 (progranulin), ceroidlipofuscinoses neuronal 13 (cathepsin F), ceroid lipofuscinoses neuronal14 (KCTD7), ceroid lipofuscinoses neuronal 15 (TBCK), and cyclindependent kinase like 5. In some embodiments, the stabilized proteincomprises a lysosomal enzyme. In some embodiments, the stabilizedprotein comprises a stabilized α-galactosidase (α-GAL) protein. In someembodiments, the stabilized α-galactosidase A (α-GAL) protein comprisesone or more non-native cysteine residues selected from the groupconsisting of: (i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the stabilized protein comprises a stabilized palmitoylprotein thioesterase 1 (PPT1). In some embodiments, the stabilized PPT1protein comprises non-native cysteine residues A171C and A183C. In someembodiments, the stabilized protein has a longer half-life at pH 7.4compared to a corresponding protein without the non-native cysteines. Insome embodiments, the stabilized protein can replace a protein defectiveor deficient in the genetic disorder. In some embodiments, thestabilized protein can reduce or slow one or more symptoms associatedwith the genetic disorder. In some embodiments, the stabilized proteinis more effective at reducing or slowing one or more symptoms of thegenetic disorder, compared to an unstabilized protein. In someembodiments, the genetic disorder is a neurological disorder. In someembodiments, the genetic disorder is a lysosomal storage disorder. Insome embodiments, the genetic disorder is selected from the groupconsisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabrydisease, Gaucher disease type I, Gaucher disease type II, Gaucherdisease type III, Pompe disease, Tay Sachs disease, Sandhoff disease,metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis typeII, mucolipidosis type III, mucolipidosis type IV, Hurler disease,Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B,Sanfilippo disease type C, Sanfilippo disease type D, Morquio diseasetype A, Morquio disease type B, Maroteau-Lamy disease, Sly disease,Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pickdisease type C1, Niemann-Pick disease type C2, Schindler disease type I,Schindler disease type II, adenosine deaminase severe combinedimmunodeficiency (ADA-SCID), chronic granulomatous disease (CGD),infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis,and CDKL5 deficiency disease. In some embodiments, the gene therapyvector is a viral vector selected from the group consisting of anadenovirus vector, an adeno-associated virus vector, a retrovirusvector, a lentivirus vector, and a herpes virus vector. In someembodiments, the adeno-associated virus is a serotype selected from thegroup consisting of: AAV-1, AAV-2, AAV-3, AAV-4, AAV-5, AAV-6, AAV-7,AAV-8, AAV-9, AAV-10, AAV-11, AAV-12, AAV-13, AAV rh.74, AAV-B1 andAAV-hu68. In some embodiments, the nucleic acid construct is comprisedin a viral vector genome. In some embodiments, the viral vector genomecomprises a recombinant AAV (rAAV) genome. In some embodiments, the rAAVgenome comprises a self-complementary genome. In some embodiments, therAAV genome comprises a single-stranded genome. In some embodiments, therAAV genome comprises a first inverted terminal repeat and a secondinverted terminal repeat. In some embodiments, the AAV inverted terminalrepeats are AAV2 inverted terminal repeats. In some embodiments, therAAV genome further comprises an SV40 intron. In some embodiments, therAAV genome further comprises a poly-adenylation sequence. In someembodiments, the construct further comprises a nucleic acid sequenceencoding an α-GAL protein, wherein the nucleic acid sequence is at least85% identical to one of SEQ ID NOs: 7-12. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding an α-GALprotein, wherein the α-GAL protein comprises a sequence at least 85%identical to one of SEQ ID NOs: 1-6. In some embodiments, the constructfurther comprises a nucleic acid sequence encoding an α-GAL protein,wherein the nucleic acid sequence comprises the sequence of one of SEQID NOs: 8-12. In some embodiments, the construct further comprises anucleic acid sequence encoding an α-GAL protein, wherein the α-GALprotein comprises the sequence of one of SEQ ID NOs: 2-6. In someembodiments, the construct further comprises a nucleic acid sequenceencoding a PPT1 protein, wherein the nucleic acid sequence is at least85% identical to one of SEQ ID NOs: 15-16. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding a PPT1protein, wherein the PPT1 protein comprises a sequence at least 85%identical to one of SEQ ID NOs: 13-14. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding a PPT1protein, wherein the nucleic acid sequence comprises the sequence of SEQID NO: 16. In some embodiments, the construct further comprises anucleic acid sequence encoding a PPT1 protein, wherein the PPT1 proteincomprises the sequence of SEQ ID NO: 14. In some embodiments, theconstruct further comprises a promoter sequence. In some embodiments,the promoter is a constitutive promoter. In some embodiments, thepromoter is a tissue-specific promoter. In some embodiments, theconstruct further comprises one or more nucleic acid sequences selectedfrom the group consisting of: a Kozak sequence, a CrPV IRES, a nucleicacid sequence encoding a linker, a nucleic acid sequence encoding asignal sequence, and a nucleic acid sequence encoding an IGF2 peptide.In some embodiments, the signal peptide sequence comprises a bindingimmunoglobulin protein (Bip) signal sequence. In some embodiments, thesignal peptide sequence comprises the Bip signal sequence comprises anamino acid sequence at least 90% identical to an amino acid sequenceselected from the group consisting of SEQ ID NOs: 29-33. In someembodiments, the construct further comprises an internal ribosomal entrysequence (IRES). In some embodiments, the IRES comprises a cricketparalysis virus (CrPV) IRES. In some embodiments, the construct furthercomprises a nucleic acid sequence encoding a variant IGF2 (vIGF2)peptide. In some embodiments, the vIGF2 peptide comprising an amino acidsequence at least 90% identical to an amino acid sequence selected fromthe group consisting of SEQ ID NOs: 17-27. In some embodiments, thenucleic acid sequence encoding the vIGF2 peptide is 5′ to the nucleicacid sequence encoding the stabilized form of the protein. In someembodiments, the nucleic acid sequence encoding the vIGF2 peptide is 3′to the nucleic acid sequence encoding the stabilized form of theprotein. In some embodiments, the construct is packaged within a viralcapsid. In some embodiments, the excipient is selected from the groupconsisting of saline, maleic acid, tartaric acid, lactic acid, citricacid, acetic acid, sodium bicarbonate, sodium phosphate, histidine,glycine, sodium chloride, potassium chloride, calcium chloride, zincchloride, water, dextrose, N-methylpyrrolidone, dimethyl sulfoxide,N,N-dimethylacetamide, ethanol, propylene glycol, polyethylene glycol,diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate.

In further aspects, there are provided methods for treating a geneticdisorder in a subject comprising administering to the subject atherapeutically effective amount of a gene therapy vector comprising anucleic acid construct comprising: a nucleic acid encoding a stabilizedform of a protein for treating a genetic disorder or a pharmaceuticalcompositions thereof. In some embodiments, the stabilized form comprisesone or more non-native cysteine residues that form a disulfide bridgebetween non-native cysteines within the protein or between non-nativecysteines of two monomers of the protein. In some embodiments, theprotein is selected from the group consisting of alpha-galactosidase A,β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase,glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase,N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase(NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase,glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase,tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs),ceroid lipofuscinoses neuronal 1, ceroid lipofuscinoses neuronal 2,ceroid lipofuscinoses neuronal 3, ceroid lipofuscinoses neuronal 4,ceroid lipofuscinoses neuronal 5, ceroid lipofuscinoses neuronal 6,ceroid lipofuscinoses neuronal 7, ceroid lipofuscinoses neuronal 8,ceroid lipofuscinoses neuronal 9, ceroid lipofuscinoses neuronal 10,ceroid lipofuscinoses neuronal 11, ceroid lipofuscinoses neuronal 12,ceroid lipofuscinoses neuronal 13, ceroid lipofuscinoses neuronal 14,ceroid lipofuscinoses neuronal 15, ceroid lipofuscinoses neuronal 16,and cyclin dependent kinase like 5. In some embodiments, the protein isselected from the group consisting of alpha-galactosidase A,β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase,glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase,N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase(NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase,glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase,tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs),ceroid lipofuscinoses neuronal 4, ceroid lipofuscinoses neuronal 10(cathepsin D), ceroid lipofuscinoses neuronal 11 (progranulin), ceroidlipofuscinoses neuronal 13 (cathepsin F), ceroid lipofuscinoses neuronal14 (KCTD7), ceroid lipofuscinoses neuronal 15 (TBCK), and cyclindependent kinase like 5. In some embodiments, the stabilized proteincomprises a lysosomal enzyme. In some embodiments, the stabilizedprotein comprises a stabilized α-galactosidase (α-GAL) protein. In someembodiments, the stabilized α-galactosidase A (α-GAL) protein comprisesone or more non-native cysteine residues D233C and I359C. In someembodiments, the stabilized protein comprises a stabilized palmitoylprotein thioesterase 1 (PPT1). In some embodiments, the stabilized PPT1protein comprises non-native cysteine residues A171C and A183C. In someembodiments, the stabilized protein has a longer half-life at pH 7.4compared to a corresponding protein without the non-native cysteines. Insome embodiments, the stabilized protein can replace a protein defectiveor deficient in the genetic disorder. In some embodiments, thestabilized protein can reduce or slow one or more symptoms associatedwith the genetic disorder. In some embodiments, the stabilized proteinis more effective at reducing or slowing one or more symptoms of thegenetic disorder, compared to an unstabilized protein. In someembodiments, the genetic disorder is a neurological disorder. In someembodiments, the genetic disorder is a lysosomal storage disorder. Insome embodiments, the genetic disorder is selected from the groupconsisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabrydisease, Gaucher disease type I, Gaucher disease type II, Gaucherdisease type III, Pompe disease, Tay Sachs disease, Sandhoff disease,metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis typeII, mucolipidosis type III, mucolipidosis type IV, Hurler disease,Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B,Sanfilippo disease type C, Sanfilippo disease type D, Morquio diseasetype A, Morquio disease type B, Maroteau-Lamy disease, Sly disease,Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pickdisease type C1, Niemann-Pick disease type C2, Schindler disease type I,Schindler disease type II, adenosine deaminase severe combinedimmunodeficiency (ADA-SCID), chronic granulomatous disease (CGD),infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis,and CDKL5 deficiency disease. In some embodiments, the gene therapyvector is a viral vector selected from the group consisting of anadenovirus vector, an adeno-associated virus vector, a retrovirusvector, a lentivirus vector, and a herpes virus vector. In someembodiments, the adeno-associated virus is a serotype selected from thegroup consisting of: AAV-1, AAV-2, AAV-3, AAV-4, AAV-5, AAV-6, AAV-7,AAV-8, AAV-9, AAV-10, AAV-11, AAV-12, AAV-13, AAV rh.74, AAV-B1 andAAV-hu68. In some embodiments, the nucleic acid construct is comprisedin a viral vector genome. In some embodiments, the viral vector genomecomprises a recombinant AAV (rAAV) genome. In some embodiments, In someembodiments, In some embodiments, In some embodiments, In someembodiments, the rAAV genome comprises a self-complementary genome. Insome embodiments, the rAAV genome comprises a single-stranded genome. Insome embodiments, the rAAV genome comprises a first inverted terminalrepeat and a second inverted terminal repeat. In some embodiments, theAAV inverted terminal repeats are AAV2 inverted terminal repeats. Insome embodiments, the rAAV genome further comprises an SV40 intron. Insome embodiments, the rAAV genome further comprises a poly-adenylationsequence. In some embodiments, the construct further comprises a nucleicacid sequence encoding an α-GAL protein, wherein the nucleic acidsequence is at least 85% identical to one of SEQ ID NOs: 7-12. In someembodiments, the construct further comprises a nucleic acid sequenceencoding an α-GAL protein, wherein the α-GAL protein comprises asequence at least 85% identical to one of SEQ ID NOs: 1-6. In someembodiments, the construct further comprises a nucleic acid sequenceencoding an α-GAL protein, wherein the nucleic acid sequence comprisesthe sequence of one of SEQ ID NOs: 8-12. In some embodiments, theconstruct further comprises a nucleic acid sequence encoding an α-GALprotein, wherein the α-GAL protein comprises the sequence of one of SEQID NOs: 2-6. In some embodiments, the construct further comprises anucleic acid sequence encoding a PPT1 protein, wherein the nucleic acidsequence is at least 85% identical to one of SEQ ID NOs: 15-16. In someembodiments, the construct further comprises a nucleic acid sequenceencoding a PPT1 protein, wherein the PPT1 protein comprises a sequenceat least 85% identical to one of SEQ ID NOs: 13-14. In some embodiments,the construct further comprises a nucleic acid sequence encoding a PPT1protein, wherein the nucleic acid sequence comprises the sequence of SEQID NO: 16. In some embodiments, the construct further comprises anucleic acid sequence encoding a PPT1 protein, wherein the PPT1 proteincomprises the sequence of SEQ ID NO: 14. In some embodiments, theconstruct further comprises a promoter sequence. In some embodiments,the promoter is a constitutive promoter. In some embodiments, thepromoter is a tissue-specific promoter. In some embodiments, theconstruct further comprises one or more nucleic acid sequences selectedfrom the group consisting of: a Kozak sequence, a CrPV IRES, a nucleicacid sequence encoding a linker, a nucleic acid sequence encoding asignal sequence, and a nucleic acid sequence encoding an IGF2 peptide.In some embodiments, the signal peptide sequence comprises a bindingimmunoglobulin protein (Bip) signal sequence. In some embodiments, thesignal peptide sequence comprises the Bip signal sequence comprises anamino acid sequence at least 90% identical to an amino acid sequenceselected from the group consisting of SEQ ID NOs: 29-33. In someembodiments, the construct further comprises an internal ribosomal entrysequence (IRES). In some embodiments, the IRES comprises a cricketparalysis virus (CrPV) IRES. In some embodiments, the construct furthercomprises a nucleic acid sequence encoding a variant IGF2 (vIGF2)peptide. In some embodiments, the vIGF2 peptide comprising an amino acidsequence at least 90% identical to an amino acid sequence selected fromthe group consisting of SEQ ID NOs: 17-27. In some embodiments, thenucleic acid sequence encoding the vIGF2 peptide is 5′ to the nucleicacid sequence encoding the stabilized form of the protein. In someembodiments, the nucleic acid sequence encoding the vIGF2 peptide is 3′to the nucleic acid sequence encoding the stabilized form of theprotein. In some embodiments, the construct is packaged within a viralcapsid. In some embodiments, the gene therapy vector or pharmaceuticalcomposition is delivered by intrathecal, intracerebroventricular,intraperenchymal, or intravenous injection, or a combination thereof. Insome embodiments, the gene therapy vector or pharmaceutical compositionreduces or slows one or more symptoms of the genetic disorder in thesubject. In some embodiments, the genetic disorder is a lysosomalstorage disorder. In some embodiments, the genetic disorder is selectedfrom the group consisting of aspartylglucosaminuria, batten disease,cystinosis, Fabry disease, Gaucher disease type I, Gaucher disease typeII, Gaucher disease type III, Pompe disease, Tay Sachs disease, Sandhoffdisease, metachomatic leukodystrophy, mucolipidosis type I,mucolipidosis type II, mucolipidosis type III, mucolipidosis type IV,Hurler disease, Hunter disease, Sanfilippo disease type A, Sanfilippodisease type B, Sanfilippo disease type C, Sanfilippo disease type D,Morquio disease type A, Morquio disease type B, Maroteau-Lamy disease,Sly disease, Niemann-Pick disease type A, Niemann-Pick disease type B,Niemann-Pick disease type C1, Niemann-Pick disease type C2, Schindlerdisease type I, Schindler disease type II, adenosine deaminase severecombined immunodeficiency (ADA-SCID), chronic granulomatous disease(CGD), neuronal ceroid lipofuscinosis, and CDKL5 deficiency disorder.

In additional aspects, there are provided stabilized humanα-galactosidase A (α-GAL) dimers. In some embodiments stabilized α-GALdimers comprise one or more non-native cysteine residues, wherein theone or more non-native cysteine residues form at least oneintermolecular disulfide bond connecting a first subunit and a secondsubunit of the α-GAL dimer. In some embodiments, the one or morenon-native cysteine residues are selected from the group consisting of:(i) D233C and I359C; and (ii) M51C and G360C. In some embodiments, theone or more non-native cysteine residues comprise D233C and I359C. Insome embodiments, the one or more non-native cysteine residues compriseM51C and G360C. In some embodiments, the one or more non-native cysteineresidues comprise i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the polypeptide has a sequence at least 90% identical toone of SEQ ID NOs: 1-6. In some embodiments, the polypeptide is encodedby a nucleic acid at least 85% identical to one of SEQ ID NOs: 7-12. Insome embodiments, the polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide. In some embodiments, thepolypeptide further comprises a variant IGF2 (vIGF2) peptide.

In further aspects, there are provided pharmaceutical compositionscomprising stabilized human α-GAL dimers and a pharmaceuticallyacceptable excipient, carrier, or diluent. In some embodimentsstabilized α-GAL dimers comprise one or more non-native cysteineresidues, wherein the one or more non-native cysteine residues form atleast one intermolecular disulfide bond connecting a first subunit and asecond subunit of the α-GAL dimer. In some embodiments, the one or morenon-native cysteine residues are selected from the group consisting of:(i) D233C and I359C; and (ii) M51C and G360C. In some embodiments, theone or more non-native cysteine residues comprise D233C and I359C. Insome embodiments, the one or more non-native cysteine residues compriseM51C and G360C. In some embodiments, the one or more non-native cysteineresidues comprise i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the polypeptide has a sequence at least 90% identical toone of SEQ ID NOs: 1-6. In some embodiments, the polypeptide is encodedby a nucleic acid at least 85% identical to one of SEQ ID NOs: 7-12. Insome embodiments, the polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide. In some embodiments, thepolypeptide further comprises a variant IGF2 (vIGF2) peptide. In someembodiments, the excipient is selected from the group consisting ofsaline, maleic acid, tartaric acid, lactic acid, citric acid, aceticacid, sodium bicarbonate, sodium phosphate, histidine, glycine, sodiumchloride, potassium chloride, calcium chloride, zinc chloride, water,dextrose, N-methylpyrrolidone, dimethyl sulfoxide,N,N-dimethylacetamide, ethanol, propylene glycol, polyethylene glycol,diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate.

In additional aspects, there are provided methods for treating Fabrydisease in a subject comprising administering to the subject atherapeutically effective amount of a stabilized human α-GAL dimer orpharmaceutical composition thereof to a subject in need thereof. In someembodiments stabilized α-GAL dimers comprise one or more non-nativecysteine residues, wherein the one or more non-native cysteine residuesform at least one intermolecular disulfide bond connecting a firstsubunit and a second subunit of the α-GAL dimer. In some embodiments,the one or more non-native cysteine residues are selected from the groupconsisting of: (i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the one or more non-native cysteine residues comprise D233Cand I359C. In some embodiments, the one or more non-native cysteineresidues comprise M51C and G360C. In some embodiments, the one or morenon-native cysteine residues comprise i) D233C and I359C; and (ii) M51Cand G360C. In some embodiments, the polypeptide has a sequence at least90% identical to one of SEQ ID NOs: 1-6. In some embodiments, thepolypeptide is encoded by a nucleic acid at least 85% identical to oneof SEQ ID NOs: 7-12. In some embodiments, the polypeptide showsincreased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the polypeptide further comprises avariant IGF2 (vIGF2) peptide. In some embodiments, the excipient isselected from the group consisting of saline, maleic acid, tartaricacid, lactic acid, citric acid, acetic acid, sodium bicarbonate, sodiumphosphate, histidine, glycine, sodium chloride, potassium chloride,calcium chloride, zinc chloride, water, dextrose, N-methylpyrrolidone,dimethyl sulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol,polyethylene glycol, diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate. In some embodiments, the stabilizedhuman α-GAL dimer or pharmaceutical composition is delivered byintrathecal, intracerebroventricular, intraperenchymal, subcutaneous,intramuscular, ocular, intravenous injection, or a combination thereof.In some embodiments, the stabilized human α-GAL dimer or pharmaceuticalcomposition reduces or slows one or more symptoms of the Fabry diseasein the subject.

In additional aspects, there are provided stabilized human palmitoylprotein thioesterase 1 (PPT1) molecules. In some embodiments, thestabilized PPT1 molecule comprises one or more non-native cysteineresidues wherein the one or more non-native cysteine residues form atleast one intramolecular disulfide bond within the PPT1 molecule. Insome embodiments, the stabilized PPT1 comprises non-native cysteineresidues A171C and A183C. In some embodiments, the polypeptide has asequence at least 90% identical to one of SEQ ID NOs: 13-14. In someembodiments, the polypeptide is encoded by a nucleic acid at least 85%identical to one of SEQ ID NOs: 15-16. In some embodiments, thepolypeptide shows increased half-life at pH 7.4 compared with a wildtype PPT1 polypeptide. In some embodiments, the polypeptide furthercomprises a variant IGF2 (vIGF2) peptide.

In further aspects, there are provided pharmaceutical compositionscomprising a stabilized PPT1 and a pharmaceutically acceptableexcipient, carrier, or diluent. In some embodiments, the stabilized PPT1molecule comprises one or more non-native cysteine residues wherein theone or more non-native cysteine residues form at least oneintramolecular disulfide bond within the PPT1 molecule. In someembodiments, the stabilized PPT1 comprises non-native cysteine residuesA171C and A183C. In some embodiments, the polypeptide has a sequence atleast 90% identical to one of SEQ ID NOs: 13-14. In some embodiments,the polypeptide is encoded by a nucleic acid at least 85% identical toone of SEQ ID NOs: 15-16. In some embodiments, the polypeptide showsincreased half-life at pH 7.4 compared with a wild type PPT1polypeptide. In some embodiments, the polypeptide further comprises avariant IGF2 (vIGF2) peptide. In some embodiments, the excipient isselected from the group consisting of saline, maleic acid, tartaricacid, lactic acid, citric acid, acetic acid, sodium bicarbonate, sodiumphosphate, histidine, glycine, sodium chloride, potassium chloride,calcium chloride, zinc chloride, water, dextrose, N-methylpyrrolidone,dimethyl sulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol,polyethylene glycol, diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate.

In additional aspects, there are provided methods for treating CLN1disease in a subject comprising administering to the subject atherapeutically effective amount of a stabilized PPT1 or apharmaceutical composition thereof to a subject in need thereof. In someembodiments, the stabilized PPT1 molecule comprises one or morenon-native cysteine residues wherein the one or more non-native cysteineresidues form at least one intramolecular disulfide bond within the PPT1molecule. In some embodiments, the stabilized PPT1 comprises non-nativecysteine residues A171C and A183C. In some embodiments, the polypeptidehas a sequence at least 90% identical to one of SEQ ID NOs: 13-14. Insome embodiments, the polypeptide is encoded by a nucleic acid at least85% identical to one of SEQ ID NOs: 15-16. In some embodiments, thepolypeptide shows increased half-life at pH 7.4 compared with a wildtype PPT1 polypeptide. In some embodiments, the polypeptide furthercomprises a variant IGF2 (vIGF2) peptide. In some embodiments, theexcipient is selected from the group consisting of saline, maleic acid,tartaric acid, lactic acid, citric acid, acetic acid, sodiumbicarbonate, sodium phosphate, histidine, glycine, sodium chloride,potassium chloride, calcium chloride, zinc chloride, water, dextrose,N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, ethanol,propylene glycol, polyethylene glycol, diethylene glycol monoethylether, and surfactant polyoxyethylene-sorbitan monooleate. In someembodiments, the modified PPT1 or pharmaceutical composition isdelivered by intrathecal, intracerebroventricular, intraperenchymal,subcutaneous, intramuscular, ocular, intravenous injection, or acombination thereof.

In additional aspects, there are provided modified human α-galactosidaseA (α-GAL) polypeptides comprising cysteine substitutions of an α-GALpolypeptide sequence selected from the group consisting of: (i) D233Cand I359C; and (ii) M51C and G360C. In some embodiments, the polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence ofD233C and I359C. In some embodiments, the polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence of M51C and G360C. Insome embodiments, the polypeptide forms a homodimer. In someembodiments, the homodimer is stabilized by a disulfide bond. In someembodiments, the polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide.

In further aspects, there are provided, nucleic acid moleculescomprising a nucleic acid encoding a modified human α-GAL polypeptide.In some embodiments, the modified human α-GAL polypeptide comprisescysteine substitutions of an α-GAL polypeptide sequence selected fromthe group consisting of: (i) D233C and I359C; and (ii) M51C and G360C.In some embodiments, the polypeptide comprises cysteine substitutions ofan α-GAL polypeptide sequence of D233C and I359C. In some embodiments,the polypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of M51C and G360C. In some embodiments, the polypeptide forms ahomodimer. In some embodiments, the homodimer is stabilized by adisulfide bond. In some embodiments, the polypeptide shows increasedhalf-life at pH 7.4 compared with a wild type α-GAL polypeptide.

In further aspects, there are provided gene therapy vectors comprising anucleic acid molecule comprising a nucleic acid encoding a modifiedhuman α-GAL polypeptide. In some embodiments, the modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, the polypeptide comprisescysteine substitutions of an α-GAL polypeptide sequence of D233C andI359C. In some embodiments, the polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence of M51C and G360C. Insome embodiments, the polypeptide forms a homodimer. In someembodiments, the homodimer is stabilized by a disulfide bond. In someembodiments, the polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide.

In additional aspects, there are provided, modified humanα-galactosidase A (α-GAL) polypeptides comprising cysteine substitutionsof an α-GAL polypeptide sequence, wherein the cysteine substitutionsfacilitate disulfide bond formation between two α-GAL polypeptides toform a homodimer. In some embodiments, the polypeptide comprisescysteine substitutions of an α-GAL polypeptide sequence selected fromthe group consisting of: (i) D233C and I359C; and (ii) M51C and G360C.In some embodiments, the polypeptide comprises cysteine substitutions ofan α-GAL polypeptide sequence of D233C and I359C. In some embodiments,the polypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of M51C and G360C. In some embodiments, the polypeptide showsincreased half-life at pH 7.4 compared with a wild type α-GALpolypeptide.

In further aspects, there are provided nucleic acid molecule comprisinga nucleic acid encoding a modified human α-GAL polypeptide. In someembodiments, the modified human α-galactosidase A (α-GAL) polypeptidescomprise cysteine substitutions of an α-GAL polypeptide sequence,wherein the cysteine substitutions facilitate disulfide bond formationbetween two α-GAL polypeptides to form a homodimer. In some embodiments,the polypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, the polypeptide comprisescysteine substitutions of an α-GAL polypeptide sequence of D233C andI359C. In some embodiments, the polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence of M51C and G360C. Insome embodiments, the polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide.

In additional aspects, there are provided gene therapy vectorscomprising a nucleic acid encoding a modified human α-GAL polypeptide.In some embodiments, the modified human α-galactosidase A (α-GAL)polypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence, wherein the cysteine substitutions facilitate disulfide bondformation between two α-GAL polypeptides to form a homodimer. In someembodiments, the polypeptide comprises cysteine substitutions of anα-GAL polypeptide sequence selected from the group consisting of: (i)D233C and I359C; and (ii) M51C and G360C. In some embodiments, thepolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, the polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence ofM51C and G360C. In some embodiments, the polypeptide shows increasedhalf-life at pH 7.4 compared with a wild type α-GAL polypeptide.

In further aspects, there are provided homodimers comprising twomodified human α-GAL polypeptides, wherein each modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, each modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, each modified humanα-GAL polypeptide comprises cysteine substitutions of an α-GALpolypeptide sequence of M51C and G360C. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thehomodimer shows increased half-life at pH 7.4 compared with a wild typeα-GAL homodimer.

In additional aspects, there are provided homodimers comprising twomodified human α-GAL polypeptides, wherein each modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence, wherein the cysteine substitutions facilitate disulfide bondformation between two α-GAL polypeptides to form a homodimer. In someembodiments, the polypeptide comprises cysteine substitutions of anα-GAL polypeptide sequence selected from the group consisting of: (i)D233C and I359C; and (ii) M51C and G360C. In some embodiments, eachmodified human α-GAL polypeptide comprises cysteine substitutions of anα-GAL polypeptide sequence of D233C and I359C. In some embodiments, eachmodified human α-GAL polypeptide comprises cysteine substitutions of anα-GAL polypeptide sequence of M51C and G360C. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thehomodimer shows increased half-life at pH 7.4 compared with a wild typeα-GAL homodimer.

In further aspects, there are provided nucleic acid molecules comprisinga nucleic acid encoding a modified human α-GAL polypeptide, wherein thenucleic acid encodes a polypeptide comprising cysteine substitutions ofan α-GAL polypeptide sequence selected from the group consisting of: (i)D233C and I359C; and (ii) M51C and G360C. In some embodiments, thenucleic acid encodes a polypeptide comprising cysteine substitutions ofD233C and I359C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of M51C and G360C. In someembodiments, the polypeptide forms a homodimer. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thepolypeptide shows increased half-life at pH 7.4 compared with a wildtype α-GAL polypeptide. In some embodiments, the nucleic acid is a genetherapy construct. In some embodiments, the nucleic acid furthercomprises a promoter. In some embodiments, the promoter is aconstitutive promoter. In some embodiments, the promoter is atissue-specific promoter. In some embodiments, the nucleic acidcomprises at least a portion of a virus nucleic acid sequence. In someembodiments, the virus is selected from wherein the virus comprises aretrovirus, an adenovirus, an adeno associated virus, a lentivirus, or aherpes virus.

In additional aspects, there are provided nucleic acid moleculescomprising a nucleic acid encoding a modified human α-GAL polypeptide,wherein the nucleic acid encodes a polypeptide comprising cysteinesubstitutions of an α-GAL polypeptide sequence, wherein the cysteinesubstitutions facilitate disulfide bond formation between two α-GALpolypeptides to form a homodimer. In some embodiments, the polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequenceselected from the group consisting of: (i) D233C and I359C; and (ii)M51C and G360C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of D233C and I359C. Insome embodiments, the nucleic acid encodes a polypeptide comprisingcysteine substitutions of M51C and G360C. In some embodiments, thepolypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the polypeptideshows increased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the nucleic acid is a gene therapyconstruct. In some embodiments, the nucleic acid further comprises apromoter. In some embodiments, the promoter is a constitutive promoter.In some embodiments, the promoter is a tissue-specific promoter. In someembodiments, the nucleic acid comprises at least a portion of a virusnucleic acid sequence. In some embodiments, the virus is selected fromwherein the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus.

In additional aspects, there are provided nucleic acid constructscomprising at least one promoter and a nucleic acid encoding a modifiedhuman α-GAL polypeptide, wherein the modified human α-GAL polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequenceselected from the group consisting of: (i) D233C and I359C; and (ii)M51C and G360C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, the nucleic acidencodes a polypeptide comprising cysteine substitutions of an α-GALpolypeptide sequence of M51C and G360C. In some embodiments, thepromoter is a constitutive promoter. In some embodiments, the promoteris a tissue-specific promoter. In some embodiments, the nucleic acidconstruct comprises one or more nucleic acids from the group consistingof: a CrPV IRES, a kozak sequence, a nucleic acid encoding a linker, anucleic acid sequence encoding a leader sequence, and a nucleic acidencoding a IGF2 peptide. In some embodiments, the nucleic acid constructcomprises at least a portion of a virus nucleic acid sequence. In someembodiments, the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus. In some embodiments,the polypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the polypeptideshows increased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the nucleic acid is packaged within ina viral capsid protein. In some embodiments, the nucleic acid constructis suitable for gene therapy.

In further aspects, there are provided nucleic acid constructscomprising at least one promoter and a nucleic acid encoding a modifiedhuman α-GAL polypeptide, wherein the modified human α-GAL polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence,wherein the cysteine substitutions facilitate disulfide bond formationbetween two α-GAL polypeptides to form a homodimer. In some embodiments,the polypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, the nucleic acidencodes a polypeptide comprising cysteine substitutions of an α-GALpolypeptide sequence of M51C and G360C. In some embodiments, thepromoter is a constitutive promoter. In some embodiments, the promoteris a tissue-specific promoter. In some embodiments, the nucleic acidconstruct comprises one or more nucleic acids from the group consistingof: a CrPV IRES, a kozak sequence, a nucleic acid encoding a linker, anucleic acid sequence encoding a leader sequence, and a nucleic acidencoding a IGF2 peptide. In some embodiments, the nucleic acid constructcomprises at least a portion of a virus nucleic acid sequence. In someembodiments, the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus. In some embodiments,the polypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the polypeptideshows increased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the nucleic acid is packaged within ina viral capsid protein. In some embodiments, the nucleic acid constructis suitable for gene therapy.

In further aspects, there are provided pharmaceutical compositionscomprising (a) a modified human α-GAL polypeptide, wherein the modifiedhuman α-GAL polypeptide comprises cysteine substitutions of an α-GALpolypeptide sequence selected from the group consisting of: (i) D233Cand I359C; and (ii) M51C and G360C and (b) a pharmaceutically acceptableexcipient. In some embodiments, the modified human α-GAL polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence ofD233C and I359C. In some embodiments, the modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of M51C and G360C. In some embodiments, the modified humanα-GAL polypeptide forms a homodimer. In some embodiments, the homodimeris stabilized by a disulfide bond. In some embodiments, the modifiedhuman α-GAL polypeptide shows increased half-life at pH 7.4 comparedwith a wild type α-GAL polypeptide. In some embodiments, the excipientis selected from the group consisting of saline, maleic acid, tartaricacid, lactic acid, citric acid, acetic acid, sodium bicarbonate, sodiumphosphate, histidine, glycine, sodium chloride, potassium chloride,calcium chloride, zinc chloride, water, dextrose, N-methylpyrrolidone,dimethyl sulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol,polyethylene glycol, diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate. In some embodiments, thecomposition is suitable for enzyme replacement therapy.

In additional aspects, there are provided methods of ameliorating atleast one symptom of Fabry disease in a subject in need thereof, themethod comprising administering at least one dose of a compositioncomprising a gene therapy nucleic acid construct comprising at least onepromoter and a nucleic acid encoding a modified human α-GAL polypeptide,wherein the modified human α-GAL polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence selected from the groupconsisting of: (i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the nucleic acid encodes a polypeptide comprising cysteinesubstitutions of an α-GAL polypeptide sequence of D233C and I359C. Insome embodiments, the nucleic acid encodes a polypeptide comprisingcysteine substitutions of an α-GAL polypeptide sequence of M51C andG360C. In some embodiments, the nucleic acid encodes a polypeptide whichforms a homodimer. In some embodiments, the homodimer is stabilized by adisulfide bond. In some embodiments, the nucleic acid encodes a modifiedhuman α-GAL polypeptide having increased half-life at pH 7.4 comparedwith a wild type α-GAL polypeptide. In some embodiments, the promoter isa constitutive promoter. In some embodiments, the promoter is atissue-specific promoter. In some embodiments, the nucleic acidcomprises at least a portion of a virus. In some embodiments, the virusis selected from wherein the virus comprises a retrovirus, anadenovirus, an adeno associated virus, a lentivirus, or a herpes virus.In some embodiments, the nucleic acid is packaged within in a viralcapsid protein. In some embodiments, the at least one symptom isselected from one or more of pain, skin discoloration, inability tosweat, eye cloudiness, gastrointestinal dysfunction, tinnitus, hearingloss, mitral valve prolapse, heart disease, joint pain, renal failure,and kidney dysfunction. In some embodiments, at least one symptom isreduced with a single administration of the gene therapy nucleic acidconstruct. In some embodiments, the method further comprises measuringan α-GAL activity in a tissue obtained from the subject followingtreatment.

In further aspects, there are provided methods of ameliorating at leastone symptom of Fabry disease in a subject in need thereof, the methodcomprising administering at least one dose of a composition comprising amodified human α-GAL polypeptide, wherein the modified human α-GALpolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, the modified human α-GALpolypeptide cysteine substitutions of an α-GAL polypeptide sequence ofD233C and I359C. In some embodiments, the modified human α-GALpolypeptide cysteine substitutions of an α-GAL polypeptide sequence ofM51C and G360C. In some embodiments, the modified human α-GALpolypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the modified humanα-GAL polypeptide shows increased half-life at pH 7.4 compared with awild type α-GAL polypeptide. In some embodiments, the at least onesymptom is selected from one or more of pain, skin discoloration,inability to sweat, eye cloudiness, gastrointestinal dysfunction,tinnitus, hearing loss, mitral valve prolapse, heart disease, jointpain, renal failure, and kidney dysfunction.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

An understanding of the features and advantages of the present inventionwill be obtained by reference to the following detailed description thatsets forth illustrative embodiments, in which the principles of theinvention are utilized, and the accompanying drawings of which:

FIG. 1A and FIG. 1B show the structure of α-galactosidase A (α-GAL) andthe proposed sites of amino acid substitutions.

FIG. 2A shows modified α-GAL dimer formation.

FIG. 2B shows modified α-GAL enzymatic activity.

FIG. 3A shows stability of α-GAL at pH 4.6 and pH 7.4 over 24 hours.

FIG. 3B shows stability of α-GAL at pH 4.6 and pH 7.4 over 7 days.

FIG. 4A shows uptake and enzymatic activity of modified α-GAL of Fabrypatient fibroblasts.

FIG. 4B shows reduction of globotriaosylsphingosine (lyso-Gb₃) in Fabrypatient fibroblasts.

FIG. 5 shows activity of enhanced half-life of two α-GAL disulfidedimers in Fabry disease cells.

FIG. 6 shows GB3 substrate histology in wildtype mice and GLA knockoutmice with and without treatment with modified α-GAL gene therapy.

FIG. 7 shows GLA enzyme activity in wildtype mice and GLA knockout micewith and without treatment with modified α-GAL gene therapy.

FIG. 8 shows GB3 substrate measured in kidney tissue lysate in wildtypemice and GLA knockout mice with and without treatment with modifiedα-GAL gene therapy.

FIG. 9 shows WinNonlin analysis of enzymatic activity of palmitoylprotein thioesterase 1 (PPT-1) wildtype vs Construct PPT-1 mutant overtime.

DETAILED DESCRIPTION

Provided herein are variants of polypeptides for therapeutics includingconstructs for gene therapy having cysteine substitutions which enablestabilization due to formation of disulfide bonds within the molecule orto disulfide bonds forming between the two subunits in the polypeptideto form a dimer. These disulfide bonds result in a more stablerecombinant enzyme at neutral pH, such as the pH of blood. Accordingly,a more stable polypeptide with longer half-life is provided that isuseful for treatment of diseases resulting from mutations, includingdiseases resulting from mutation of α-GAL, such as Fabry disease; ormutation of PPT-1, such as CLN1 disease. Polypeptide variants (alsotermed “modified polypeptides”) herein include but are not limited tovariants of α-GAL and PPT-1.

Modified α-GAL Polypeptides

Provided herein are modified α-GAL polypeptides comprising cysteinesubstitutions of an α-GAL polypeptide sequence. Contemplatedsubstitutions provided herein include: (i) R49C and G361C; (ii) R49C andG360C; (iii) D233C and I359C; (iv) M5 IC and G360C; and (v) S276C. Insome embodiments, the polypeptide comprises cysteine substitutions of anα-GAL polypeptide sequence selected from the group consisting of: (i)D233C and I359C; and (ii) M51C and G360C. In some embodiments, thepolypeptide comprises cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, the polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence of M5IC and G360C. The modified α-GAL polypeptides a can form a homodimer isstabilized by at least one, more preferably two intermolecular disulfidebonds. The modified α-GAL polypeptides polypeptide shows increasedhalf-life at pH 7.4 compared with a wildtype α-GAL polypeptide.

Wild type and exemplary Modified α-GAL sequences are provided in Table 1

TABLE 1 α-GAL Polypeptide Sequences α-GAL SEQ variant Sequence ID NO:Human MQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWERFMCN 1 α-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL wildQADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFA typeDWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQK (NP_PNYTEIRQYCNHWRNFADIDDSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDM 000160.1)LVIGNFGLSWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQEIGGPRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL HumanMQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWE C FMCN 2 α-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL R49C-QADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFA G361CDWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQKPNYTEIRQYCNHWRNFADIDDSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDMLVIGNFGLSWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQEIG C PRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL HumanMQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWE C FMCN 3 A-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL R49C-QADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFA G360CDWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQKPNYTEIRQYCNHWRNFADIDDSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDMLVIGNFGLSWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQEI C GPRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL HumanMQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWERF C CN 4 α-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL M51C-QADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFA G360C DWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQKPNYTEIRQYCNHWRNFADIDDSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDMLVIGNFGLSWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQEI C GPRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL HumanMQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWERFMCN 5 α-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL D233C-QADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFA I359CDWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQKPNYTEIRQYCNHWRNFADI C DSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDMLVIGNFGLSWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQE C GGPRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL HumanMQLRNPELHLGCALALRFLALVSWDIPGARALDNGLARTPTMGWLHWERFMCN 6 α-GALLDCQEEPDSCISEKLFMEMAELMVSEGWKDAGYEYLCIDDCWMAPQRDSEGRL S276CQADPQRFPHGIRQLANYVHSKGLKLGIYADVGNKTCAGFPGSFGYYDIDAQTFADWGVDLLKFDGCYCDSLENLADGYKHMSLALNRTGRSIVYSCEWPLYMWPFQKPNYTEIRQYCNHWRNFADIDDSWKSIKSILDWTSFNQERIVDVAGPGGWNDPDM LVIGNFGL CWNQQVTQMALWAIMAAPLFMSNDLRHISPQAKALLQDKDVIAINQDPLGKQGYQLRQGDNFEVWERPLSGLAWAVAMINRQEIGGPRSYTIAVASLGKGVACNPACFITQLLPVKRKLGFYEWTSRLRSHINPTGTVLLQLENTMQMSLKDLL

Also provided herein are modified α-GAL polypeptides comprising apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 90% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 95% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 96% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 97% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 98% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having at least 99% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence containing cysteine residues at positions 51and 360 and having more than 99% identity to a sequence set forth as SEQID NO: 4. In some embodiments, modified α-GAL polypeptides comprise apolypeptide with a sequence set forth as SEQ ID NO: 4.

Also provided herein are modified α-GAL polypeptides comprising apolypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 90% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 95% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 96% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 97% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 98% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having at least 99% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions233 and 359 and having more than 99% identity to a sequence set forth asSEQ ID NO: 5. In some embodiments, modified α-GAL polypeptides comprisea polypeptide with a sequence set forth as SEQ ID NO: 5.

Also provided herein are homodimers comprising two modified α-GALpolypeptides, wherein each modified α-GAL polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence selected from the groupconsisting of: (i) R49C and G361C; (ii) R49C and G360C; (iii) D233C andI359C; (iv) M51C and G360C; and (v) S276C. In some embodiments, eachmodified α-GAL polypeptide comprises cysteine substitutions of an α-GALpolypeptide sequence selected from the group consisting of: (i) D233Cand I359C; and (ii) M51C and G360C. In some embodiments, each modifiedα-GAL polypeptide comprises cysteine substitutions of an α-GALpolypeptide sequence of D233C and I359C. In some embodiments, eachmodified α-GAL polypeptide comprises cysteine substitutions of an α-GALpolypeptide sequence of M51C and G360C. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thehomodimer shows increased half-life at pH 7.4 compared with a wild typeα-GAL homodimer.

In some embodiments, modified α-GAL polypeptides have an increasedhalf-life at pH 4.6. In some embodiments, the half-life at pH 4.6 is atleast 50% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 4.6 is at least 150% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH4.6 is at least 200% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 4.6 is at least 250% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH4.6 is at least 300% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 4.6 is at least 350% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH4.6 is at least 400% greater than a wild type α-GAL polypeptide.

In some embodiments, the modified α-GAL dimer has a half-life at pH 4.6that is increased by at least a factor of about 2, 2.5, 3, 3.5, 4, 4.5or 5 compared to the half-life of wild type α-GAL at pH 4.6. Morepreferably, the modified α-GAL dimer has a half-life at pH 4.6 that isincreased by at least a factor of about 3, 3.5, or 4 compared to thehalf-life of wild type α-GAL polypeptide at pH 4.6.

In some embodiments, the modified α-GAL dimer has an intracellularhalf-life at that is increased by at least a factor of about 2, 2.5, 3,3.5, 4, 4.5 or 5 compared to the intracellular half-life of wild typehuman α-GAL. More preferably, the modified α-GAL dimer has anintracellular half-life that is increased by at least a factor of about3, 3.5, or 4, 4.5 or 5 compared to the intracellular half-life of wildtype α-GAL polypeptide.

The modified α-GAL dimer has a substantially increased half-life at pH7.4 compared to wild type human α-GAL.

Nucleic Acids Encoding Modified α-GAL Polypeptides

Also provided herein are nucleic acid molecules comprising nucleic acidsencoding a modified α-GAL polypeptide. Contemplated nucleic acidsinclude those encoding a polypeptide comprising cysteine substitutionsof an α-GAL polypeptide sequence including: (i) R49C and G361C; (ii)R49C and G360C; (iii) D233C and I359C; (iv) M51C and G360C; and (v)S276C. In some embodiments, the nucleic acid encodes a polypeptidecomprising cysteine substitutions of an α-GAL polypeptide sequenceselected from the group consisting of: (i) D233C and I359C; and (ii)M51C and G360C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of D233C and I359C. Insome embodiments, the nucleic acid encodes a polypeptide comprisingcysteine substitutions of M51C and G360C. In some embodiments, thepolypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the polypeptideshows increased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the nucleic acid is a gene therapyconstruct. In some embodiments, the nucleic acid further comprises apromoter. In some embodiments, the promoter is a constitutive promoter.In some embodiments, the promoter is a tissue-specific promoter. In someembodiments, the nucleic acid comprises at least a portion of a virusnucleic acid sequence. In some embodiments, the virus is selected fromwherein the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus.

Also provided herein are nucleic acid constructs comprising at least onepromoter and a nucleic acid encoding a modified α-GAL polypeptide.Modified α-GAL polypeptides are contemplated to comprise cysteinesubstitutions of an α-GAL polypeptide sequence including: (i) R49C andG361C; (ii) R49C and G360C; (iii) D233C and I359C; (iv) M51C and G360C;and (v) S276C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of an α-GAL polypeptidesequence selected from the group consisting of: (i) D233C and I359C; and(ii) M51C and G360C. In some embodiments, the nucleic acid encodes apolypeptide comprising cysteine substitutions of an α-GAL polypeptidesequence of D233C and I359C. In some embodiments, the nucleic acidencodes a polypeptide comprising cysteine substitutions of an α-GALpolypeptide sequence of M51C and G360C. In some embodiments, thepromoter is a constitutive promoter. In some embodiments, the promoteris a tissue-specific promoter. In some embodiments, the nucleic acidconstruct comprises at least a portion of a virus nucleic acid sequence.In some embodiments, the virus comprises a retrovirus, an adenovirus, anadeno associated virus, a lentivirus, or a herpes virus. In someembodiments, the polypeptide forms a homodimer. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thepolypeptide shows increased half-life at pH 7.4 compared with a wildtype α-GAL polypeptide. In some embodiments, the nucleic acid ispackaged within in a viral capsid protein. In some embodiments, thenucleic acid construct is suitable for gene therapy.

TABLE 2 α-GAL Nucleic Acid Sequences α-GAL SEQ variant Sequence ID NO:α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccacgtacctg  7wildggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgtypeggagcgatcatgtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctatcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccctcagcgctacctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagtatggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtaggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacattgatgattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctcagctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggagattggtggacctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttttgcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccacgtacctg  8R49C-ggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgG361CggagTgcttcatgtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctcttcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccacagcgctttcctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagttttggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtttggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacattgatgattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctcagctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggagattggt T g Ccctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttttgcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccctcgtttcctg 9 R49C-ggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgG360C ggag Tgcttcatgtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctcttcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccctcagcgctttcctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagttttggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtttggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacattgatgattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctcagctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggagatt Tgtggacctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttttgcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccctcgtacctg10 M51C-ggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgG360C ggagcgcttcT GCtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctcttcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccctcagcgctacctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagttaggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtaggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacattgatgattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctcagctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggagatt Tgtggacctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttttgcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccctcgtttcctg11 D233C-ggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgI359Cggagcgcttcatgtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctcttcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccctcagcgctacctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagttttggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtttggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacatt TGC gattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctcagctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggag TGC ggtggacctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttagcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa α-GALatgcagctgaggaacccagaactacatctgggctgcgcgcttgcgcttcgcttcctggccctcgtacctg12 S276Cggacatccctggggctagagcactggacaatggattggcaaggacgcctaccatgggctggctgcactgggagcgcttcatgtgcaaccttgactgccaggaagagccagattcctgcatcagtgagaagctcttcatggagatggcagagctcatggtctcagaaggctggaaggatgcaggttatgagtacctctgcattgatgactgttggatggctccccaaagagattcagaaggcagacttcaggcagaccctcagcgctacctcatgggattcgccagctagctaattatgttcacagcaaaggactgaagctagggatttatgcagatgttggaaataaaacctgcgcaggcttccctgggagttttggatactacgacattgatgcccagacctttgctgactggggagtagatctgctaaaatttgatggttgttactgtgacagtttggaaaatttggcagatggttataagcacatgtccttggccctgaataggactggcagaagcattgtgtactcctgtgagtggcctctttatatgtggccctttcaaaagcccaattatacagaaatccgacagtactgcaatcactggcgaaattttgctgacattgatgattcctggaaaagtataaagagtatcttggactggacatcttttaaccaggagagaattgttgatgttgctggaccagggggttggaatgacccagatatgttagtgattggcaactttggcctc Tgctggaatcagcaagtaactcagatggccctctgggctatcatggctgctcctttattcatgtctaatgacctccgacacatcagccctcaagccaaagctctccttcaggataaggacgtaattgccatcaatcaggaccccttgggcaagcaagggtaccagcttagacagggagacaactttgaagtgtgggaacgacctctctcaggcttagcctgggctgtagctatgataaaccggcaggagattggtggacctcgctcttataccatcgcagttgcttccctgggtaaaggagtggcctgtaatcctgcctgcttcatcacacagctcctccctgtgaaaaggaagctagggttctatgaatggacttcaaggttaagaagtcacataaatcccacaggcactgttttgcttcagctagaaaatacaatgcagatgtcattaaaagacttactttaa

In some embodiments, nucleic acids encoding modified α-GAL polypeptidesherein have an increased half-life compared with a wild type α-GALpolypeptide. In some embodiments, the half-life is at least 50% greaterthan a wild type α-GAL polypeptide. In some embodiments, the half-lifeis at least 150% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life is at least 200% greater than a wild typeα-GAL polypeptide. In some embodiments, the half-life is at least 250%greater than a wild type α-GAL polypeptide. In some embodiments, thehalf-life is at least 300% greater than a wild type α-GAL polypeptide.In some embodiments, the half-life is at least 350% greater than a wildtype α-GAL polypeptide.

Modified PPT-1 Polypeptides

Provided herein are modified PPT-1 polypeptides comprising cysteinesubstitutions of a PPT-1 polypeptide sequence. Contemplatedsubstitutions provided herein include A171C and A183C. In someembodiments, the polypeptide comprises cysteine substitutions of a PPT-1polypeptide sequence of A171C and A183C. The modified PPT-1 polypeptideis stabilized by at least one, more preferably two intramoleculardisulfide bonds. The modified PPT-1 polypeptides polypeptide showincreased half-life at pH 7.4 compared with a wildtype PPT-1polypeptide.

Wild type and exemplary Modified PPT-1 are provided in Table 3.

TABLE 3 PPT-1 Polypeptide Sequences PPT-1 SEQ variant Sequence ID NO:Human MASPGCLWLLAVALLPWTCASRALQHLDPPAPLPLVIWHGMGDSCCNPLSMGAI 13 PPT-1KKMVEKKIPGIYVLSLEIGKTLMEDVENSFFLNVNSQVTTVCQALAKDPKLQQGY wildNAMGFSQGGQFLRAVAQRCPSPPMINLISVGGQHQGVFGLPRCPGESSHICDFIRK typeTLNAGAYSKVVQERLVQAEYWHDPIKEDVYRNHSIFLADINQERGINESYKKNL (NP_MALKKFVMVKFLNDSIVDPVDSEWFGFYRSGQAKETIPLQETSLYTQDRLGLKE 000301.1)MDNAGQLVFLATEGDHLQLSEEWFYAHIIPFLG PPT-1MASPGCLWLLAVALLPWTCASRALQHLDPPAPLPLVIWHGMGDSCCNPLSMGAI 14 A171CKKMVEKKIPGIYVLSLEIGKTLMEDVENSFFLNVNSQVTTVCQALAKDPKLQQGY A183CNAMGFSQGGQFLRAVAQRCPSPPMINLISVGGQHQGVFGLPRCPGESSHICDFIRK TLNAG CYSKVVQERLVQ C EYWHDPIKEDVYRNHSIFLADINQERGINESYKKNLMALKKFVMVKFLNDSIVDPVDSEWFGFYRSGQAKETIPLQETSLYTQDRLGLKEMDNAGQLVFLATEGDHLQLSEEWFYAHIIPFLG

Also provided herein are modified PPT-1 polypeptides comprising apolypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 90% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 95% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 96% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 97% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 98% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having at least 99% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence containing cysteine residues at positions171 and 183 and having more than 99% identity to a sequence set forth asSEQ ID NO: 14. In some embodiments, modified PPT-1 polypeptides comprisea polypeptide with a sequence set forth as SEQ ID NO: 14.

In some embodiments, modified PPT-1 polypeptides have an increasedhalf-life at pH 4.6. In some embodiments, the half-life at pH 4.6 is atleast 50% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 4.6 is at least 150% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH4.6 is at least 200% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 4.6 is at least 250% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH4.6 is at least 300% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 4.6 is at least 350% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH4.6 is at least 400% greater than a wild type PPT-1 polypeptide.

In some embodiments, the modified PPT-1 polypeptide has a half-life atpH 4.6 that is increased by at least a factor of about 2, 2.5, 3, 3.5,4, 4.5 or 5 compared to the half-life of wild type PPT-1 at pH 4.6. Morepreferably, the modified PPT-1 polypeptide has a half-life at pH 4.6that is increased by at least a factor of about 3, 3.5, or 4 compared tothe half-life of wild type PPT-1 polypeptide at pH 4.6.

In some embodiments, the modified PPT-1 polypeptide has an intracellularhalf-life at that is increased by at least a factor of about 2, 2.5, 3,3.5, 4, 4.5 or 5 compared to the intracellular half-life of wild typehuman α-GAL. More preferably, the modified PPT-1 polypeptide has anintracellular half-life that is increased by at least a factor of about3, 3.5, or 4, 4.5 or 5 compared to the intracellular half-life of wildtype PPT-1 polypeptide.

The modified PPT-1 polypeptide has a substantially increased half-lifeat pH 7.4 compared to wild type human α-GAL.

Nucleic Acids Encoding Modified PPT-1 Polypeptides

Also provided herein are nucleic acid molecules comprising nucleic acidsencoding a modified PPT-1 polypeptide. Contemplated nucleic acidsinclude those encoding a polypeptide comprising cysteine substitutionsof a PPT-1 polypeptide sequence including: A171C and A183C. In someembodiments, the nucleic acid encodes a polypeptide comprising cysteinesubstitutions of A171C and A183C. In some embodiments, the polypeptideis stabilized by a disulfide bond. In some embodiments, the polypeptideshows increased half-life at pH 7.4 compared with a wild type PPT-1polypeptide. In some embodiments, the nucleic acid is a gene therapyconstruct. In some embodiments, the nucleic acid further comprises apromoter. In some embodiments, the promoter is a constitutive promoter.In some embodiments, the promoter is a tissue-specific promoter. In someembodiments, the nucleic acid comprises at least a portion of a virusnucleic acid sequence. In some embodiments, the virus is selected fromwherein the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus.

TABLE 4 PT-1 Nucleic Acid Sequences PPT-1 SEQ variant Sequence ID NO:PPT-1 TTATTTTGATTCACCGCAGAGGGCGGTCTACGAGAGCGCAGAG 15 wildCCCCACTCGGCCAGCGGGGTCTGGCGGGGGACCTGTCGCGCTG typeAAAGCTCCAGGGTAGGGCCGACGCCCATCAGGCTGGGCATCCGTTCGGGATGCGCAGGTTGCGATCTGCAACCGGCGGCGCCACGCCCAGGCGGGCGGAGCGCGGTTCCCGGAGTCTCGCGCCCGCGGTCATGTGACACAGCGAAGATGGCGTCGCCCGGCTGCCTGTGGCTCTTGGCTGTGGCTCTCCTGCCATGGACCTGCGCTTCTCGGGCGCTGCAGCATCTGGACCCGCCGGCGCCGCTGCCGTTGGTGATCTGGCATGGGATGGGAGACAGCTGTTGCAATCCCTTAAGCATGGGTGCTATTAAAAAAATGGTGGAGAAGAAAATACCTGGAATTTACGTCTTATCTTTAGAGATTGGGAAGACCCTGATGGAGGACGTGGAGAACAGCTTCTTCTTGAATGTCAATTCCCAAGTAACAACAGTGTGTCAGGCACTTGCTAAGGATCCTAAATTGCAGCAAGGCTACAATGCTATGGGATTCTCCCAGGGAGGCCAATTTCTGAGGGCAGTGGCTCAGAGATGCCCTTCACCTCCCATGATCAATCTGATCTCGGTTGGGGGACAACATCAAGGTGTTTTTGGACTCCCTCGATGCCCAGGAGAGAGCTCTCACATCTGTGACTTCATCCGAAAAACACTGAATGCTGGGGCGTACTCCAAAGTTGTTCAGGAACGCCTCGTGCAAGCCGAATACTGGCATGACCCCATAAAGGAGGATGTGTATCGCAACCACAGCATCTTCTTGGCAGATATAAATCAGGAGCGGGGTATCAATGAGTCCTACAAGAAAAACCTGATGGCCCTGAAGAAGTTTGTGATGGTGAAATTCCTCAATGATTCCATTGTGGACCCTGTAGATTCGGAGTGGTTTGGATTTTACAGAAGTGGCCAAGCCAAGGAAACCATTCCCTTACAGGAGACCTCCCTGTACACACAGGACCGCCTGGGGCTAAAGGAAATGGACAATGCAGGACAGCTAGTGTTTCTGGCTACAGAAGGGGACCATCTTCAGTTGTCTGAAGAATGGTTTTATGCCCACATCATACCATTCCTTGGATGAAACCCGTATAGTTCACAATAGAGCTCAGGGAGCCCCTAACTCTTCCAAACCACATGGGAGACAGTTTCCTTCATGCCCAAGCCTGAGCTCAGATCCAGCTTGCAACTAATCCTTCTATCATCTAACATGCCCTACTTGGAAAGATCTAAGATCTGAATCTTATCCTTTGCCATCTTCTGTTACCATATGGTGTTGAATGCAAGTTTAATTACCATGGAGATTGTTTTACAAACTTTTGATGTGGTCAAGTTCAGTTTTAGAAAAGGGAGTCTGTTCCAGATCAGTGCCAGAACTGTGCCCAGGCCCAAAGGAGACAACTAACTAAAGTAGTGAGATAGATTCTAAGGGCAAACATTTTTCCAAGTCTTGCCATATTTCAAGCAAAGAGGTGCCCAGGCCTGAGGTACTCACATAAATGCTTTGTTTTGCTGGTGATTTAACCAGTGCTTGGAAAAATCTTGCTTGGCTATTTCTGCATCATTTCTTAAGGCTGCCTTCCTCTCTCAGTACGTTGCCCTCTGTGCTATCATCTTATCATCAATTATTAGACAAATCCCACTGGCCTACAGTCTTGCTTCTGCAGCACCCACTTTGTCTCCTCAGGTAGTGATGAATTAGTTGCTGTCACAAAAGGAGGGAAGTAGCACCCAAATTAAGTTGCTTAAGAGAGGAAATGTACATCTTGTATAACTTAGGGAGCGAAGAAAATGTAGGCGCGAAAGTGAAAAGTGAGGCAGCTAGTTCTTCCTATTCCATTCTCGACCAACCTGCCCTTTCTTAATATGACTAGTGGTCTTGATGCTAGAGTCAACTTACTCTGTTGCTGGCTTTAGCAGAGAATAGGAGGAACCATATGAAAAAGATCAGGCTTTCTGACTTCCATCCCCAAAACACATTTACCAGCATACTCCAAACTGTTTCTGATGTGTTCCATGAGAAAAGGATTGTTTGCTCAAAAAGCTTGGAAAATACTACACACTCCCTTTCTCCTTCTGGAGATCAACCCACATTAGAGTGTCTAAGGACTCCTGAGAATTCCTGTTACAGTAAACAAAACTAACGTAATCTACCATTTCCTACACTATTTGAGCATGGAAATCATAGTCCCCACTCTGTGAAAACTTAACGCTTTTTGGAAGACATTTCTGTAGCATGTCAGTTTGGAGAAATGATGAGCTACGCCTTGATGAAAGAACCGTGTTGGTGCTGCTAAGTTTAGCCATTATGGTTTTTCCTTTCTCTCTCTTAAGCCTTATTCTTCAACTAAAAGATGAGGATTAAGAGCAAGAAGTTGGGGGGGATGTGAAAATAATTTTATGAGGTTGTCTAAA ATAAAGAGTAGTTTCTTATC PPT-1ATGGCATCACCGGGTTGCCTCTGGTTGTTGGCCGTTGCGTTGCT 16 A171CTCCGTGGACATGTGCATCAAGAGCTCTTCAACATCTGGATCCCC A183CCAGCTCCCCTGCCGCTCGTAATCTGGCACGGGATGGGGGATTCATGTTGTAACCCGTTGTCAATGGGCGCGATAAAAAAGATGGTTGAAAAGAAGATTCCAGGCATCTACGTTCTGTCCCTGGAAATCGGTAAGACACTGATGGAAGACGTGGAGAACTCCTTCTTTCTCAACGTCAATAGTCAGGTCACTACCGTCTGTCAAGCATTGGCAAAGGACCCTAAACTTCAGCAGGGGTACAATGCGATGGGGTTTAGCCAGGGCGGACAGTTTCTTAGAGCCGTCGCACAGCGCTGTCCATCTCCCCCGATGATTAACCTTATATCTGTCGGGGGACAACACCAGGGTGTTTTTGGTCTTCCTCGCTGTCCTGGTGAAAGCTCCCACATCTGTGATTTCATACGCAAAACGTTGAACGCAGGATGCTATAGTAAAGTCGTCCAAGAACGGCTTGTTCAATGCGAGTATTGGCATGACCCAATAAAAGAAGACGTTTATAGGAATCACTCTATCTTCTTGGCCGATATCAACCAAGAACGCGGAATCAACGAAAGCTACAAAAAGAATCTTATGGCTCTCAAGAAATTTGTTATGGTGAAATTCCTTAATGACTCTATAGTAGATCCTGTCGATTCAGAATGGTTCGGGTTCTACAGGTCTGGCCAGGCGAAGGAGACTATTCCCCTCCAAGAAACGTCTCTCTATACACAAGACAGACTCGGACTGAAAGAGATGGATAATGCGGGCCAGTTGGTCTTCTTGGCTACGGAAGGCGATCATCTCCAACTCTCCGAAGAGTGGTTCTATGCCCATATAATCCCGTTCCTGG GCTAA

In some embodiments, nucleic acids encoding modified PPT-1 polypeptidesherein have an increased half-life compared with a wild type PPT-1polypeptide. In some embodiments, the half-life is at least 50% greaterthan a wild type PPT-1 polypeptide. In some embodiments, the half-lifeis at least 150% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life is at least 200% greater than a wild typePPT-1 polypeptide. In some embodiments, the half-life is at least 250%greater than a wild type PPT-1 polypeptide. In some embodiments, thehalf-life is at least 300% greater than a wild type PPT-1 polypeptide.In some embodiments, the half-life is at least 350% greater than a wildtype PPT-1 polypeptide.

IGF2 Peptides

In some cases, modified polypeptides herein, such as modified α-GAL ormodified PPT-1 polypeptides herein are fused to an Insulin-Like GrowthFactor 2 (IGF2) peptide for targeting modified polypeptides to thelysosome where they are needed. Variants in the IGF2 peptide sequencemaintain high affinity binding to IGF2/CI-MPR and eliminate binding toIGF1, insulin receptors, and IGF binding proteins (IGFBP). The variantIGF2 peptide is substantially more selective and has reduced safetyrisks compared to conventional IGF2 fusion proteins. IGF2 peptidesherein include those having an amino acid sequence ofAYRPSETLCGGELVDTLQFVCGDRGFYFSRPASRVSRRSRGIVEECCFRSCDLALLETYCATPAKS E(SEQ ID NO: 17). Additional IGF2 peptides have variant amino acidsequences optimized for improved targeting. Variant IGF2 peptidesinclude variant amino acids at positions, 26, 27, 43, 48, 49, 50, 54,55, or 65 of a wild type IGF2 sequence. These include substitutions atF26, Y27, V43, F48, R49, S50, A54, L55, or K65 of SEQ ID NO: 17. In someembodiments, the IGF2 peptide has a sequence having one or moresubstitutions from the group consisting of F26S, Y27L, V43L, F48T, R49S,S50I, A54R, L55R, and K65R. In some embodiments, the IGF2 peptide has asequence having a substitution of F26S. In some embodiments, the IGF2peptide has a sequence having a substitution of Y27L. In someembodiments, the IGF2 peptide has a sequence having a substitution ofV43L. In some embodiments, the IGF2 peptide has a sequence having asubstitution of F48T. In some embodiments, the IGF2 peptide has asequence having a substitution of R49S. In some embodiments, the IGF2peptide has a sequence having a substitution of S50I. In someembodiments, the IGF2 peptide has a sequence having a substitution ofA54R. In some embodiments, the IGF2 peptide has a sequence having asubstitution of L55R. In some embodiments, the IGF2 peptide has asequence having a substitution of K65R. In some embodiments, the IGF2peptide has a sequence having a substitution of F26S, Y27L, V43L, F48T,R49S, S50I, A54R, and L55R. In some embodiments, the IGF2 peptide has anN-terminal deletion. In some embodiments, the IGF2 peptide has anN-terminal deletion of one amino acid. In some embodiments, the IGF2peptide has an N-terminal deletion of two amino acids. In someembodiments, the IGF2 peptide has an N-terminal deletion of three aminoacids. In some embodiments, the IGF2 peptide has an N-terminal deletionof three amino acids. In some embodiments, the IGF2 peptide has anN-terminal deletion of four amino acids. In some embodiments, the IGF2peptide has an N-terminal deletion of five amino acids. In someembodiments, the IGF2 peptide has an N-terminal deletion of six aminoacids. In some embodiments, the IGF2 peptide has an N-terminal deletionof seven amino acids. In some embodiments, the IGF2 peptide has anN-terminal deletion of seven amino acids and a substitution of Y27L andK65R.

Additional substitutions are contemplated for decreasing instabilitywhile maintaining CI-MPR binding affinity. These substitutions arecontemplated to be combined with any other substitution describedherein. In some embodiments, the IGF2 peptide has a sequence having asubstitution of L17N. In some embodiments, the IGF2 peptide has asequence having a substitution of P31G. In some embodiments, the IGF2peptide has a sequence having a substitution of R38G. In someembodiments, the IGF2 peptide has a sequence having a substitution ofE45W. In some embodiments, the IGF2 peptide has a sequence having asubstitution of S50G. In some embodiments, the IGF2 peptide has asequence having substitutions of R38G and E45W. In some embodiments, theIGF2 peptide has a sequence having substitutions of R38G, E45W, andS50G. In some embodiments, the IGF2 peptide has a sequence havingsubstitutions of P31G, R38G, E45W, and S50G. In some embodiments, theIGF2 peptide has a sequence having substitutions of L17N, P31G, R38G,E45W, and S50G. Exemplary peptide sequences are represented by SEQ IDNOs: 17-27.

TABLE 5 IGF Peptide Sequences (variant residues are underlined) SEQ IDPeptide Sequence NO Wild type AYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 17VSRRSRGIVEECCFRSCDLALLETYCATPAKSE F26SAYRPSETLCGGELVDTLQFVCGDRGSYFSRPASR 18 VSRRSRGIVEECCFRSCDLALLETYCATPAKSEY27L AYRPSETLCGGELVDTLQFVCGDRGFLFSRPASRV 19SRRSRGIVEECCFRSCDLALLETYCATPAKSE V43L AYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR20 VSRRSRGILEECCFRSCDLALLETYCATPAKSE F48TAYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 21 VSRRSRGIVEECCTRSCDLALLETYCATPAKSER49S AYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 22VSRRSRGIVEECCFSSCDLALLETYCATPAKSE S50IAYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 23 VSRRSRGIVEECCFRICDLALLETYCATPAKSEA54R AYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 24VSRRSRGIVEECCFRSCDLRLLETYCATPAKSE L55RAYRPSETLCGGELVDTLQFVCGDRGFYFSRPASR 25 VSRRSRGIVEECCFRSCDLARLETYCATPAKSEF26S, Y27L, V43L, AYRPSETLCGGELVDTLQFVCGDRGSLFSRPASRV 26F48T, R49S, S50I, SRRSRGILEECCTSICDLRRLETYCATPAKSE A54R, L55RΔ1-6, Y27L, K65R TLCGGELVDTLQFVCGDRGFLFSRPASRVSRRSRG 27IVEECCFRSCDLALLETYCATPARSE

Internal Ribosomal Entry Sequences

Nucleic acids encoding a modified polypeptides herein, such as nucleicacids encoding modified α-GAL and PP-1 polypeptides, in someembodiments, further comprise an internal ribosome entry sequence (IRES)for increasing gene expression by bypassing the bottleneck oftranslation initiation. Suitable internal ribosomal entry sequences foroptimizing expression for gene therapy include but are not limited to acricket paralysis virus (CrPV) IRES, a picornavirus IRES, an AphthovirusIRES, a Kaposi's sarcoma-associated herpesvirus IRES, a Hepatitis AIRES, a Hepatitis C IRES, a Pestivirus IRES, a Cripavirus IRES, aRhopalosiphum padi virus IRES, a Merek's disease virus IRES, and othersuitable IRES sequences. In some embodiments, the gene therapy constructcomprises a CrPV IRES. In some embodiments, the CrPV IRES has a nucleicacid sequence of

(SEQ ID NO: 28) CGGUGUCGAAGUAGAAUUUCUAUCUCGACACGCGGCCUUCCAAGCAGUUAGGGAAACCGACUUCUUUGAAGAAGAAAGCUGACUAUGUGAUCUUAUUAAAAUUAGGUUAAAUUUCGAGGUUAAAAAUAGUUUUAAUAUUGCUAUAGUCUUAGAGGUCUUGUAUAUUUAUACUUACCACACAAGAUGGACCGGAGCAGCCCUCCAAUAUCUAGUGUACCCUCGUGCUCGCUCAAACAUUAAGUGGUGUUGUGCGAA AAGAAUCUCACUUCAAGAA

Signal Sequence

Provided herein are nucleic acid molecules comprising nucleic acidsencoding modified polypeptides, such as modified α-GAL polypeptides ormodified PPT-1 polypeptides, wherein the nucleic acid molecules furthercomprise a signal peptide, which improves secretion of the therapeuticprotein from the cell transduced with the gene therapy construct. Thesignal peptide in some embodiments improves protein processing oftherapeutic proteins, and facilitates translocation of the nascentpolypeptide-ribosome complex to the ER and ensuring properco-translational and post-translational modifications. In someembodiments, the signal peptide is located (i) in an upstream positionof the signal translation initiation sequence, (ii) in between thetranslation initiation sequence and the therapeutic protein, or (iii) adownstream position of the therapeutic protein. Signal peptides usefulin gene therapy constructs include but are not limited to bindingimmunoglobulin protein (BiP) signal peptide from the family of HSP70proteins (e.g., HSPA5, heat shock protein family A member 5), andvariants thereof. These signal peptides have ultrahigh affinity to thesignal recognition particle. Examples of BiP amino acid sequences areprovided in Table 6 below. In some embodiments, the signal peptide hasan amino acid sequence that is at least 90% identical to a sequenceselected from the group consisting of SEQ ID Nos: 29-33. In someembodiments, the signal peptide differs from a sequence selected fromthe group consisting of SEQ ID Nos: 29-33 by 5 or fewer, 4 or fewer, 3or fewer, 2 or fewer, or 1 amino acid.

TABLE 6 Signal Sequences Signal Sequence Amino Acid Sequence SEQ ID NO:Native human Bip MKLSLVAAMLLLLSAARA 29 Modified Bip-1MKLSLVAAMLLLLSLVAAMLLLLSAARA 30 Modified Bip-2 MKLSLVAAMLLLLWVALLLLSAARA31 Modified Bip-3 MKLSLVAAMLLLLSLVALLLLSAARA 32 Modified Bip-4MKLSLVAAMLLLLALVALLLLSAARA 33

Kozak Sequence

Provided herein are nucleic acid molecules comprising nucleic acidsencoding modified polypeptides, such as modified α-GAL polypeptides ormodified PPT-1 polypeptides, wherein the nucleic acid molecules furthercomprise a nucleic acid having a kozak sequence, which aids ininitiation of translation of the mRNA. Kozak sequences contemplatedherein have a consensus sequence of gccRccAUGG (SEQ ID NO: 34) where alowercase letter denotes the most common base at the position and thebase varies, uppercase letters indicate highly conserved bases that onlyvary rarely change. R indicates that a purine (adenine or guanine) isalways observed at that position. The sequence in parentheses (gcc) isof uncertain significance.

Therapeutic Protein

Gene therapy constructs provided herein comprise a nucleic acid encodinga stabilized form of a protein for treating a genetic disorder. Thetherapeutic protein expressed from the gene therapy construct replacesthe absent or defective protein. Therapeutic proteins, therefore, arechosen based on the genetic defect in need of treatment in anindividual. Stabilized forms herein comprise one or more non-nativecysteine residues that form a disulfide bridge between the non-nativecysteines within the protein or between non-native cysteines of twomonomers of the protein.

In some embodiments, gene therapy constructs herein encode an enzyme,such as an enzyme having a genetic defect in an individual with alysosomal storage disorder. In some embodiments, enzymes encoded by genetherapy constructs provided herein include but are not limited toalpha-galactosidase A, β-glucocerebrosidase, glucocerebrosidase,lysosomal acid lipase, glycosaminoglycan alpha-L-iduronidase,alpha-L-iduronidase, N-sulfoglucosamine sulfohydrolase (SGSH),N-acetyl-alpha-glucosaminidase (NAGLU), iduronate-2-sulfatase,N-acetylgalactosamine-6-sulfatase, glycosaminoglycanN-acetylgalactosamine 4-sulfatase, alpha-glucosidase, tripeptidylpeptidase 1 (TPP1), palmitoyl protein thioesterases, ceroidlipofuscinoses neuronal 1, ceroid lipofuscinoses neuronal 2, ceroidlipofuscinoses neuronal 3, ceroid lipofuscinoses neuronal 4, ceroidlipofuscinoses neuronal 5, ceroid lipofuscinoses neuronal 6, ceroidlipofuscinoses neuronal 7, ceroid lipofuscinoses neuronal 8, ceroidlipofuscinoses neuronal 9, ceroid lipofuscinoses neuronal 10, ceroidlipofuscinoses neuronal 11, ceroid lipofuscinoses neuronal 12, ceroidlipofuscinoses neuronal 13, ceroid lipofuscinoses neuronal 14, ceroidlipofuscinoses neuronal 15, ceroid lipofuscinoses neuronal 16, andcyclin dependent kinase like 5.

Gene Therapy Vectors and Compositions

Provided herein are gene therapy vectors comprising a nucleic acidconstruct comprising: a nucleic acid encoding a stabilized form of aprotein for treating a neurological or genetic disorder, the stabilizedform comprising one or more non-native cysteine residues that form adisulfide bridge between non-native cysteines within the protein orbetween non-native cysteines of two monomers of the protein. In someembodiments, the stabilized form comprises a modified α-GAL polypeptideor a modified PPT-1 polypeptide.

In some embodiments, the nucleic acid encoding a modified polypeptide iscloned into a number of types of vectors. For example, in someembodiments, the nucleic acid is cloned into a vector including, but notlimited to a plasmid, a phagemid, a phage derivative, an animal virus,and a cosmid. Vectors of particular interest include expression vectors,replication vectors, probe generation vectors, and sequencing vectors.

Further, the expression vector encoding the modified polypeptide isprovided to a cell in the form of a viral vector. Viral vectortechnology is described, e.g., in Sambrook et al., 2012, MolecularCloning: A Laboratory Manual, volumes 1-4, Cold Spring Harbor Press,NY), and in other virology and molecular biology manuals. Viruses, whichare useful as vectors include, but are not limited to, retroviruses,adenoviruses, adeno-associated viruses, herpes viruses, andlentiviruses. In general, a suitable vector contains an origin ofreplication functional in at least one organism, a promoter sequence,convenient restriction endonuclease sites, and one or more selectablemarkers (e.g., WO 01/96584; WO 01/29058; and U.S. Pat. No. 6,326,193).

Also provided herein are compositions and systems for gene transfer. Anumber of virally based systems have been developed for gene transferinto mammalian cells. For example, retroviruses provide a convenientplatform for gene delivery systems. A selected gene, in someembodiments, is inserted into a vector and packaged in retroviralparticles using suitable techniques. The recombinant virus is thenisolated and delivered to cells of the subject either in vivo or exvivo. A number of retroviral systems are suitable for gene therapy. Insome embodiments, adenovirus vectors are used. A number of adenovirusvectors are suitable for gene therapy. In some embodiments,adeno-associated virus vectors are used. A number of adeno-associatedviruses are suitable for gene therapy. In one embodiment, lentivirusvectors are used.

Gene therapy constructs provided herein comprise a vector (or genetherapy expression vector) into which the gene of interest is cloned orotherwise which includes the gene of interest in a manner such that thenucleotide sequences of the vector allow for the expression(constitutive or otherwise regulated in some manner) of the gene ofinterest. The vector constructs provided herein include any suitablegene expression vector that is capable of being delivered to a tissue ofinterest and which will provide for the expression of the gene ofinterest in the selected tissue of interest.

In some embodiments, the vector is an adeno-associated virus (AAV)vector because of the capacity of AAV vectors to cross the blood-brainbarrier and transduction of neuronal tissue. In methods provided herein,AAV of any serotype is contemplated to be used. The serotype of theviral vector used in certain embodiments is selected from the groupconsisting of AAV1 vector, an AAV2 vector, an AAV3 vector, an AAV4vector, an AAV5 vector, an AAV6 vector, an AAV7 vector, an AAV8 vector,an AAV9 vector, an AAVrhS vector, an AAVrh10 vector, an AAVrh33 vector,an AAVrh34 vector, an AAVrh74 vector, an AAV Anc80 vector, an AAVPHP.Bvector, an AAVhu68 vector, an AAV-DJ vector, and others suitable forgene therapy.

AAV vectors are DNA parvoviruses that are nonpathogenic for mammals.Briefly, AAV-based vectors have the rep and cap viral genes that accountfor 96% of the viral genome removed, leaving the two flanking 145 basepair inverted terminal repeats (ITR) which are used to initiate viralDNA replication, packaging, and integration.

Further embodiments include use of other serotype capsids to create anAAV1 vector, an AAV2 vector, an AAV3 vector, an AAV4 vector, an AAV5vector, an AAV6 vector, an AAV7 vector, an AAV8 vector, an AAV9 vector,an AAVrhS vector, an AAVrh10 vector, an AAVrh33 vector, an AAVrh34vector, an AAVrh74 vector, an AAV Anc80 vector, an AAVPHP.B vector, anAAV-DJ vector, and others suitable for gene therapy. Optionally, the AAVviral capsid is AAV2/9, AAV9, AAVrhS, AAVrh10, AAVAnc80, or AAV PHP.B.

Additional promoter elements, e.g., enhancers, regulate the frequency oftranscriptional initiation. Typically, these are located in the region30-110 bp upstream of the start site, although a number of promotershave been shown to contain functional elements downstream of the startsite as well. The spacing between promoter elements frequently isflexible, so that promoter function is preserved when elements areinverted or moved relative to one another. In the thymidine kinase (tk)promoter, the spacing between promoter elements is often increased to 50bp apart before activity begins to decline. Depending on the promoter,it appears that individual elements function either cooperatively orindependently to activate transcription.

An example of a promoter that is capable of expressing a stabilizedprotein, such as a modified α-GAL polypeptide or a modified PPT-1polypeptide transgene in a mammalian T-cell is the EF1a promoter. Thenative EF1a promoter drives expression of the alpha subunit of theelongation factor-1 complex, which is responsible for the enzymaticdelivery of aminoacyl tRNAs to the ribosome. The EF1a promoter has beenextensively used in mammalian expression plasmids and has been shown tobe effective in driving expression from transgenes cloned into alentiviral vector (see, e.g., Milone et al., Mol. Ther. 17(8): 1453-1464(2009)). Another example of a promoter is the immediate earlycytomegalovirus (CMV) promoter sequence. This promoter sequence is astrong constitutive promoter sequence capable of driving high levels ofexpression of any polynucleotide sequence operatively linked thereto.However, other constitutive promoter sequences are sometimes also used,including, but not limited to the simian virus 40 (SV40) early promoter,mouse mammary tumor virus (MMTV), human immunodeficiency virus (HIV)long terminal repeat (LTR) promoter, MoMuLV promoter, an avian leukemiavirus promoter, an Epstein-Barr virus immediate early promoter, a Roussarcoma virus promoter, as well as human gene promoters such as, but notlimited to, the actin promoter, the myosin promoter, the elongationfactor-1a promoter, the hemoglobin promoter, and the creatine kinasepromoter. Further, gene therapy vectors are not contemplated to belimited to the use of constitutive promoters. Inducible promoters arealso contemplated here. The use of an inducible promoter provides amolecular switch capable of turning on expression of the polynucleotidesequence which it is operatively linked when such expression is desired,or turning off the expression when expression is not desired. Examplesof inducible promoters include, but are not limited to a metallothioninepromoter, a glucocorticoid promoter, a progesterone promoter, and atetracycline-regulated promoter. In some embodiments, the promoter is anα-GAL promoter.

In order to assess the expression of a modified polypeptide theexpression vector to be introduced into a cell often contains either aselectable marker gene or a reporter gene or both to facilitateidentification and selection of expressing cells from the population ofcells sought to be transfected or infected through viral vectors. Inother aspects, the selectable marker is often carried on a separatepiece of DNA and used in a co-transfection procedure. Both selectablemarkers and reporter genes are sometimes flanked with appropriateregulatory sequences to enable expression in the host cells. Usefulselectable markers include, for example, antibiotic-resistance genes,such as neo and the like.

Methods of introducing and expressing genes into a cell are suitable formethods herein. In the context of an expression vector, the vector isreadily introduced into a host cell, e.g., mammalian, bacterial, yeast,or insect cell by any method in the art. For example, the expressionvector is transferred into a host cell by physical, chemical, orbiological means.

Physical methods for introducing a polynucleotide into a host cellinclude calcium phosphate precipitation, lipofection, particlebombardment, microinjection, gene gun, electroporation, and the like.Methods for producing cells comprising vectors and/or exogenous nucleicacids are suitable for methods herein (see, e.g., Sambrook et al., 2012,Molecular Cloning: A Laboratory Manual, volumes 1-4, Cold Spring HarborPress, NY). One method for the introduction of a polynucleotide into ahost cell is calcium phosphate transfection

Chemical means for introducing a polynucleotide into a host cell includecolloidal dispersion systems, such as macromolecule complexes,nanocapsules, microspheres, beads, and lipid-based systems includingoil-in-water emulsions, micelles, mixed micelles, and liposomes. Anexemplary colloidal system for use as a delivery vehicle in vitro and invivo is a liposome (e.g., an artificial membrane vesicle). Other methodsof state-of-the-art targeted delivery of nucleic acids are available,such as delivery of polynucleotides with targeted nanoparticles or othersuitable sub-micron sized delivery system.

In the case where a non-viral delivery system is utilized, an exemplarydelivery vehicle is a liposome. The use of lipid formulations iscontemplated for the introduction of the nucleic acids into a host cell(in vitro, ex vivo or in vivo). In another aspect, the nucleic acid isassociated with a lipid. The nucleic acid associated with a lipid, insome embodiments, is encapsulated in the aqueous interior of a liposome,interspersed within the lipid bilayer of a liposome, attached to aliposome via a linking molecule that is associated with both theliposome and the oligonucleotide, entrapped in a liposome, complexedwith a liposome, dispersed in a solution containing a lipid, mixed witha lipid, combined with a lipid, contained as a suspension in a lipid,contained or complexed with a micelle, or otherwise associated with alipid. Lipid, lipid/DNA or lipid/expression vector associatedcompositions are not limited to any particular structure in solution.For example, in some embodiments, liposomes are present in a bilayerstructure, as micelles, or with a “collapsed” structure. Alternately,liposomes are simply interspersed in a solution, possibly formingaggregates that are not uniform in size or shape. Lipids are fattysubstances which are, in some embodiments, naturally occurring orsynthetic lipids. For example, lipids include the fatty droplets thatnaturally occur in the cytoplasm as well as the class of compounds whichcontain long-chain aliphatic hydrocarbons and their derivatives, such asfatty acids, alcohols, amines, amino alcohols, and aldehydes.

Lipids suitable for use are obtained from commercial sources. Forexample, in some embodiments, dimyristyl phosphatidylcholine (“DMPC”) isobtained from Sigma, St. Louis, Mo.; in some embodiments, dicetylphosphate (“DCP”) is obtained from K & K Laboratories (Plainview, N.Y.);cholesterol (“Choi”), in some embodiments, is obtained fromCalbiochem-Behring; dimyristyl phosphatidylglycerol (“DMPG”) and otherlipids are often obtained from Avanti Polar Lipids, Inc. (Birmingham,Ala.). Stock solutions of lipids in chloroform or chloroform/methanolare often stored at about −20° C. Chloroform is used as the only solventsince it is more readily evaporated than methanol. “Liposome” is ageneric term encompassing a variety of single and multilamellar lipidvehicles formed by the generation of enclosed lipid bilayers oraggregates. Liposomes are often characterized as having vesicularstructures with a phospholipid bilayer membrane and an inner aqueousmedium. Multilamellar liposomes have multiple lipid layers separated byaqueous medium. They form spontaneously when phospholipids are suspendedin an excess of aqueous solution. The lipid components undergoself-rearrangement before the formation of closed structures and entrapwater and dissolved solutes between the lipid bilayers (Ghosh et al.,1991 Glycobiology 5: 505-10). However, compositions that have differentstructures in solution than the normal vesicular structure are alsoencompassed. For example, the lipids, in some embodiments, assume amicellar structure or merely exist as nonuniform aggregates of lipidmolecules. Also contemplated are lipofectamine-nucleic acid complexes.

Regardless of the method used to introduce exogenous nucleic acids intoa host cell or otherwise expose a cell to the a modified α-GALpolypeptide in order to confirm the presence ofthe recombinant DNAsequence in the host cell, a variety of assays are contemplated to beperformed. Such assays include, for example, “molecular biological”assays suitable for methods herein, such as Southern and Northernblotting, RT-PCR and PCR; “biochemical” assays, such as detecting thepresence or absence of a particular peptide, e.g., by immunologicalmeans (ELISAs and western blots) or by assays described herein toidentify agents falling within the scope herein.

The present disclosure further provides a vector comprising a modifiedpolypeptide encoding nucleic acid molecule. In one aspect, a therapeuticfusion protein vector is capable of being directly transduced into acell. In one aspect, the vector is a cloning or expression vector, e.g.,a vector including, but not limited to, one or more plasmids (e.g.,expression plasmids, cloning vectors, minicircles, minivectors, doubleminute chromosomes), retroviral and lentiviral vector constructs. In oneaspect, the vector is capable of expressing the modified polypeptideconstruct in mammalian cells. In one aspect, the mammalian cell is ahuman cell.

Pharmaceutical Compositions

Provided herein are pharmaceutical compositions comprising a modifiedpolypeptide a stabilized form of a protein for treating a geneticdisorder, the stabilized form comprising one or more non-native cysteineresidues that form a disulfide bridge between non-native cysteineswithin the protein or between non-native cysteines of two monomers ofthe protein and (ii) a pharmaceutically acceptable excipient. In someembodiments, the modified polypeptide forms a homodimer. In someembodiments, the homodimer is stabilized by a disulfide bond. In someembodiments, the modified polypeptide shows increased half-life at pH7.4 compared with a wild type polypeptide.

Additionally provided herein are pharmaceutical compositions comprising(i) a modified α-GAL polypeptide, wherein the modified α-GAL polypeptidecomprises cysteine substitutions of an α-GAL polypeptide sequence and(ii) a pharmaceutically acceptable excipient. Contemplated substitutionsinclude: (i) D233C and I359C; and (ii) M51C and G360C. In someembodiments, the modified α-GAL polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence of D233C and I359C. Insome embodiments, the modified α-GAL polypeptide comprises cysteinesubstitutions of an α-GAL polypeptide sequence of M51C and G360C. Insome embodiments, the modified α-GAL polypeptide forms a homodimer. Insome embodiments, the homodimer is stabilized by a disulfide bond. Insome embodiments, the modified α-GAL polypeptide shows increasedhalf-life at pH 7.4 compared with a wild type α-GAL polypeptide. In someembodiments, the composition comprises a chaperone. In some embodiments,the chaperone comprises Migalastat.

Further provided herein are pharmaceutical compositions comprising (i) amodified PPT-1 polypeptide, wherein the modified PPT-1 polypeptidecomprises cysteine substitutions of a PPT-1 polypeptide sequence and(ii) a pharmaceutically acceptable excipient. Contemplated substitutionsinclude A171C and A183C. In some embodiments, the modified PPT-1polypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the modified PPT-1polypeptide shows increased half-life at pH 7.4 compared with a wildtype PPT-1 polypeptide. In some embodiments, the composition comprises achaperone.

Suitable excipients for pharmaceutical compositions herein include butare not limited to saline, maleic acid, tartaric acid, lactic acid,citric acid, acetic acid, sodium bicarbonate, sodium phosphate,histidine, glycine, sodium chloride, potassium chloride, calciumchloride, zinc chloride, water, dextrose, N-methylpyrrolidone, dimethylsulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol,polyethylene glycol, diethylene glycol monoethyl ether, and surfactantpolyoxyethylene-sorbitan monooleate.

In some embodiments, pharmaceutical compositions herein comprisemodified α-GAL polypeptides herein having an increased half-life at pH4.6 compared with a wild type α-GAL polypeptide. In some embodiments,the half-life at pH 4.6 is at least 50% greater than a wild type α-GALpolypeptide. In some embodiments, the half-life at pH 4.6 is at least150% greater than a wild type α-GAL polypeptide. In some embodiments,the half-life at pH 4.6 is at least 200% greater than a wild type α-GALpolypeptide. In some embodiments, the half-life at pH 4.6 is at least250% greater than a wild type α-GAL polypeptide. In some embodiments,the half-life at pH 4.6 is at least 300% greater than a wild type α-GALpolypeptide. In some embodiments, the half-life at pH 4.6 is at least350% greater than a wild type α-GAL polypeptide. In some embodiments,the half-life at pH 4.6 is at least 400% greater than a wild type α-GALpolypeptide.

In some embodiments, pharmaceutical compositions herein comprisemodified PPT-1 polypeptides herein having an increased half-life at pH4.6 compared with a wild type PPT-1 polypeptide. In some embodiments,the half-life at pH 4.6 is at least 50% greater than a wild type PPT-1polypeptide. In some embodiments, the half-life at pH 4.6 is at least150% greater than a wild type PPT-1 polypeptide. In some embodiments,the half-life at pH 4.6 is at least 200% greater than a wild type PPT-1polypeptide. In some embodiments, the half-life at pH 4.6 is at least250% greater than a wild type PPT-1 polypeptide. In some embodiments,the half-life at pH 4.6 is at least 300% greater than a wild type PPT-1polypeptide. In some embodiments, the half-life at pH 4.6 is at least350% greater than a wild type PPT-1 polypeptide. In some embodiments,the half-life at pH 4.6 is at least 400% greater than a wild type PPT-1polypeptide.

In some embodiments, pharmaceutical compositions herein comprisemodified α-GAL polypeptides having an increased half-life at pH 7.4. Insome embodiments, the half-life at pH 7.4. is at least 50% greater thana wild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 150% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 200% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 250% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 300% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 350% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 400% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 500% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 600% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 700% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 800% greater than awild type α-GAL polypeptide. In some embodiments, the half-life at pH7.4 is at least 900% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life at pH 7.4 is at least 1000% greater than awild type α-GAL polypeptide.

In some embodiments, pharmaceutical compositions herein comprisemodified PPT-1 polypeptides having an increased half-life at pH 7.4. Insome embodiments, the half-life at pH 7.4. is at least 50% greater thana wild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 150% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 200% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 250% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 300% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 350% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 400% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 500% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 600% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 700% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 800% greater than awild type PPT-1 polypeptide. In some embodiments, the half-life at pH7.4 is at least 900% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life at pH 7.4 is at least 1000% greater than awild type PPT-1 polypeptide.

Methods of Treatment Gene Therapy Methods

Also provided herein are methods of ameliorating at least one symptom ofa genetic disease in a subject in need thereof. Some such methodscomprise administering at least one dose of a composition comprising agene therapy a nucleic acid encoding a stabilized form of a protein fortreating a genetic disorder, the stabilized form comprising one or morenon-native cysteine residues that form a disulfide bridge betweennon-native cysteines within the protein or between non-native cysteinesof two monomers of the protein. In some embodiments, the nucleic acidencodes a polypeptide which forms a homodimer. In some embodiments, thehomodimer is stabilized by a disulfide bond. In some embodiments, thenucleic acid encodes a polypeptide having increased half-life at pH 7.4compared with a wild type polypeptide. In some embodiments, the promoteris a constitutive promoter. In some embodiments, the promoter is atissue-specific promoter. In some embodiments, the nucleic acidcomprises at least a portion of a virus. In some embodiments, the virusis selected from wherein the virus comprises a retrovirus, anadenovirus, an adeno associated virus, a lentivirus, or a herpes virus.In some embodiments, the nucleic acid is packaged within in a viralcapsid protein. In some embodiments, the at least one symptom isselected from one or more of pain, skin discoloration, inability tosweat, eye cloudiness, gastrointestinal dysfunction, tinnitus, hearingloss, mitral valve prolapse, heart disease, joint pain, renal failure,and kidney dysfunction. In some embodiments, at least one symptom isreduced with a single administration of the gene therapy nucleic acidconstruct. In some embodiments, the method further comprises measuringan activity in a tissue obtained from the subject following treatment.

In some embodiments the gene therapy vector or pharmaceuticalcomposition is administered to the cerebrospinal fluid. In someembodiments, the gene therapy vector or pharmaceutical composition isdelivered by intrathecal, intracerebroventricular, intraperenchymal, orintravenous injection, or a combination thereof. In some embodiments,the gene therapy vector or pharmaceutical composition is administered byintrathecal injection. In some embodiments, the gene therapy vector orpharmaceutical composition is administered via intravenous injection.

In some embodiments, the genetic disorder is a neurological disorder. Insome embodiments, the genetic disorder is a lysosomal storage disorder.In some embodiments, genetic disorder is selected from the groupconsisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabrydisease, Gaucher disease type I, Gaucher disease type II, Gaucherdisease type III, Pompe disease, Tay Sachs disease, Sandhoff disease,metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis typeII, mucolipidosis type III, mucolipidosis type IV, Hurler disease,Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B,Sanfilippo disease type C, Sanfilippo disease type D, Morquio diseasetype A, Morquio disease type B, Maroteau-Lamy disease, Sly disease,Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pickdisease type C1, Niemann-Pick disease type C2, Schindler disease type I,Schindler disease type II, adenosine deaminase severe combinedimmunodeficiency (ADA-SCID), chronic granulomatous disease (CGD),infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis,and CDKL5 deficiency disease.

Also provided herein are methods of ameliorating at least one symptom ofFabry disease in a subject in need thereof. Some such methods compriseadministering at least one dose of a composition comprising a genetherapy nucleic acid construct comprising at least one promoter and anucleic acid encoding a modified α-GAL polypeptide comprising cysteinesubstitutions of an α-GAL polypeptide sequence. Modified α-GALpolypeptides are contemplated to comprise cysteine substitutionsincluding: (i) R49C and G361C; (ii) R49C and G360C; (iii) D233C andI359C; (iv) M51C and G360C; and (v) S276C. In some embodiments, thenucleic acid encodes a polypeptide comprising cysteine substitutions ofan α-GAL polypeptide sequence selected from the group consisting of: (i)D233C and I359C; and (ii) M51C and G360C. In some embodiments, thenucleic acid encodes a polypeptide comprising cysteine substitutions ofan α-GAL polypeptide sequence of D233C and I359C. In some embodiments,the nucleic acid encodes a polypeptide comprising cysteine substitutionsof an α-GAL polypeptide sequence of M51C and G360C. In some embodiments,the nucleic acid encodes a polypeptide which forms a homodimer. In someembodiments, the homodimer is stabilized by a disulfide bond. In someembodiments, the nucleic acid encodes a modified α-GAL polypeptidehaving increased half-life at pH 7.4 compared with a wild type α-GALpolypeptide. In some embodiments, the promoter is a constitutivepromoter. In some embodiments, the promoter is a tissue-specificpromoter. In some embodiments, the nucleic acid comprises at least aportion of a virus. In some embodiments, the virus is selected fromwherein the virus comprises a retrovirus, an adenovirus, an adenoassociated virus, a lentivirus, or a herpes virus. In some embodiments,the nucleic acid is packaged within in a viral capsid protein. In someembodiments, the at least one symptom is selected from one or more ofpain, skin discoloration, inability to sweat, eye cloudiness,gastrointestinal dysfunction, tinnitus, hearing loss, mitral valveprolapse, heart disease, joint pain, renal failure, and kidneydysfunction. In some embodiments, at least one symptom is reduced with asingle administration of the gene therapy nucleic acid construct. Insome embodiments, the method further comprises measuring an α-GALactivity in a tissue obtained from the subject following treatment. Insome embodiments, the method further comprises administering achaperone. In some embodiments, the chaperone comprises Migalastat.

Also provided herein are methods of ameliorating at least one symptom ofCLN1 disease in a subject in need thereof. Some such methods compriseadministering at least one dose of a composition comprising a genetherapy nucleic acid construct comprising at least one promoter and anucleic acid encoding a modified PPT-1 polypeptide comprising cysteinesubstitutions of PPT-1 polypeptide sequence. Modified PPT-1 polypeptidesare contemplated to comprise cysteine substitutions including A171C andA183C. In some embodiments, the nucleic acid encodes a polypeptide whichforms a homodimer. In some embodiments, the homodimer is stabilized by adisulfide bond. In some embodiments, the nucleic acid encodes a modifiedPPT-1 polypeptide having increased half-life at pH 7.4 compared with awild type PPT-1 polypeptide. In some embodiments, the promoter is aconstitutive promoter. In some embodiments, the promoter is atissue-specific promoter. In some embodiments, the nucleic acidcomprises at least a portion of a virus. In some embodiments, the virusis selected from wherein the virus comprises a retrovirus, anadenovirus, an adeno associated virus, a lentivirus, or a herpes virus.In some embodiments, the nucleic acid is packaged within in a viralcapsid protein. In some embodiments, the at least one symptom isselected from one or more of pain, skin discoloration, inability tosweat, eye cloudiness, gastrointestinal dysfunction, tinnitus, hearingloss, mitral valve prolapse, heart disease, joint pain, renal failure,and kidney dysfunction. In some embodiments, at least one symptom isreduced with a single administration of the gene therapy nucleic acidconstruct. In some embodiments, the method further comprises measuring aPPT-1 activity in a tissue obtained from the subject followingtreatment. In some embodiments, the method further comprisesadministering a chaperone. In some embodiments, the chaperone comprisesMigalastat.

In some embodiments, treatment via methods described herein delivers agene encoding a therapeutic protein to a cell in need of the therapeuticprotein. In some embodiments, the treatment delivers the gene to allsomatic cells in the individual. In some embodiments, the treatmentreplaces the defective gene in the targeted cells. In some embodiments,cells treated ex vivo to express the therapeutic protein are deliveredto the individual.

In some embodiments, gene therapy treatments herein compriseadministering a nucleic acid encoding modified α-GAL polypeptides hereinhaving an intracellular half-life that is increased by at least a factorof about 2, 2.5, 3, 3.5, 4, 4.5 or 5 compared to the half-life of wildtype human α-GAL.

Enzyme Replacement Therapy Methods

Also provided method of ameliorating at least one symptom of a geneticdisease in a subject in need thereof, the method comprisingadministering at least one dose of a composition comprising a stabilizedform of a protein for treating a genetic disorder, wherein thestabilized form comprising one or more non-native cysteine residues thatform a disulfide bridge between non-native cysteines within the proteinor between non-native cysteines of two monomers of the protein. In someembodiments, the modified polypeptide forms a homodimer. In someembodiments, the homodimer is stabilized by a disulfide bond. In someembodiments, the modified polypeptide shows increased half-life at pH7.4 compared with a wild type polypeptide. In some embodiments, the atleast one symptom is selected from one or more of mental impairment,seizures, loss of speech, and loss of motor skills. In some embodiments,the method further comprises administering a chaperone. In someembodiments, the chaperone comprises Migalastat.

In some embodiments, the composition is administered via intrathecal,intracerebroventricular, intraperenchymal, subcutaneous, intramuscular,ocular, intravenous injection, or a combination thereof

In some embodiments, the genetic disorder is a neurological disorder. Insome embodiments, the genetic disorder is a lysosomal storage disorder.In some embodiments, genetic disorder is selected from the groupconsisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabrydisease, Gaucher disease type I, Gaucher disease type II, Gaucherdisease type III, Pompe disease, Tay Sachs disease, Sandhoff disease,metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis typeII, mucolipidosis type III, mucolipidosis type IV, Hurler disease,Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B,Sanfilippo disease type C, Sanfilippo disease type D, Morquio diseasetype A, Morquio disease type B, Maroteau-Lamy disease, Sly disease,Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pickdisease type C1, Niemann-Pick disease type C2, Schindler disease type I,Schindler disease type II, adenosine deaminase severe combinedimmunodeficiency (ADA-SCID), chronic granulomatous disease (CGD),infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis,and CDKL5 deficiency disease.

Also provided method of ameliorating at least one symptom of Fabrydisease in a subject in need thereof, the method comprisingadministering at least one dose of a composition comprising a modifiedα-GAL polypeptide, wherein the modified α-GAL polypeptide comprisescysteine substitutions of an α-GAL polypeptide sequence. Contemplatedcysteine substitutions include: (i) D233C and I359C; and (ii) M51C andG360C. In some embodiments, the modified α-GAL polypeptide cysteinesubstitutions of an α-GAL polypeptide sequence of D233C and I359C. Insome embodiments, the modified α-GAL polypeptide cysteine substitutionsof an α-GAL polypeptide sequence of M51C and G360C. In some embodiments,the modified α-GAL polypeptide forms a homodimer. In some embodiments,the homodimer is stabilized by a disulfide bond. In some embodiments,the modified α-GAL polypeptide shows increased half-life at pH 7.4compared with a wild type α-GAL polypeptide. In some embodiments, the atleast one symptom is selected from one or more of pain, skindiscoloration, inability to sweat, eye cloudiness, gastrointestinaldysfunction, tinnitus, hearing loss, mitral valve prolapse, heartdisease, joint pain, renal failure, and kidney dysfunction. In someembodiments, the method further comprises administering a chaperone. Insome embodiments, the chaperone comprises Migalastat.

Also provided method of ameliorating at least one symptom of a CLN-1disease in a subject in need thereof, the method comprisingadministering at least one dose of a composition comprising a modifiedPPT-1 polypeptide, wherein the PPT-1 polypeptide comprises one or morenon-native cysteine residues that form a disulfide bridge betweennon-native cysteines within the protein or between non-native cysteinesof two monomers of the protein. Contemplated cysteine substitutionsinclude: A171C and A183C. In some embodiments, the modified PPT-1polypeptide forms a homodimer. In some embodiments, the homodimer isstabilized by a disulfide bond. In some embodiments, the modified PPT-1polypeptide shows increased half-life at pH 7.4 compared with a wildtype PPT-1 polypeptide. In some embodiments, the at least one symptom isselected from one or more of mental impairment, seizures, loss ofspeech, and loss of motor skills. In some embodiments, the methodfurther comprises administering a chaperone. In some embodiments, thechaperone comprises Migalastat.

In some embodiments, methods herein comprise administering modifiedpolypeptides herein having an increased half-life compared with a wildtype polypeptide. In some embodiments, the half-life is at least 50%greater than a wild type polypeptide. In some embodiments, the half-lifeis at least 150% greater than a wild type polypeptide. In someembodiments, the half-life is at least 200% greater than a wild typepolypeptide. In some embodiments, the half-life is at least 250% greaterthan a wild type polypeptide. In some embodiments, the half-life is atleast 300% greater than a wild type polypeptide. In some embodiments,the half-life is at least 350% greater than a wild type polypeptide.

In some embodiments, methods herein comprise administering modifiedα-GAL polypeptides herein having an increased half-life compared with awild type α-GAL polypeptide. In some embodiments, the half-life is atleast 50% greater than a wild type α-GAL polypeptide. In someembodiments, the half-life is at least 150% greater than a wild typeα-GAL polypeptide. In some embodiments, the half-life is at least 200%greater than a wild type α-GAL polypeptide. In some embodiments, thehalf-life is at least 250% greater than a wild type α-GAL polypeptide.In some embodiments, the half-life is at least 300% greater than a wildtype α-GAL polypeptide. In some embodiments, the half-life is at least350% greater than a wild type α-GAL polypeptide.

In some embodiments, methods herein comprise administering modifiedPPT-1 polypeptides herein having an increased half-life compared with awild type PPT-1 polypeptide. In some embodiments, the half-life is atleast 50% greater than a wild type PPT-1 polypeptide. In someembodiments, the half-life is at least 150% greater than a wild typePPT-1 polypeptide. In some embodiments, the half-life is at least 200%greater than a wild type PPT-1 polypeptide. In some embodiments, thehalf-life is at least 250% greater than a wild type PPT-1 polypeptide.In some embodiments, the half-life is at least 300% greater than a wildtype PPT-1 polypeptide. In some embodiments, the half-life is at least350% greater than a wild type PPT-1 polypeptide.

Definitions

Stabilized” as used herein with respect to a protein refers to amodified protein (e.g., modified to contain non-native cysteineresidues) that maintains one or more of its biological activities for aperiod of time that is longer than a corresponding protein without themodification. In some embodiments, stabilized proteins maintainbiological activity for a time that is about 10%, 20%, 30%, 40%, 50%,60%, 70%, 80%, 90%, 100%, 150%, 200%, 250%, 300%, 350%, 400%, 450% or500% longer than the corresponding protein without the modification. Insome embodiments, stabilized proteins maintain biological activity for atime that is at least 10% longer, at least 20% longer, at least 30%longer, at least 40% longer, at least 50% longer, at least 60% longer,at least 70% longer, at least 80% longer, at least 90% longer, at least100% longer, at least 150% longer, at least 200% longer, at least 250%longer, at least 300% longer %, at least 350% longer, at least 400%longer, at least 450% longer or at least 500% longer than thecorresponding protein without the modification. In some embodiments, thestabilized protein has a longer half-life compared to a correspondingprotein without the non-native cysteines. In some embodiments, thestabilized protein has a longer half-life at pH 4.0 to pH 8.0, or pH 4.0to 6.0, or pH 6.0 to 8.0 compared to a corresponding protein without thenon-native cysteines. In some embodiments, the stabilized protein has alonger half-life at pH 4.5 to 5.0 or 7.0 to 7.5 compared to acorresponding protein without the non-native cysteines. In someembodiments, the stabilized protein has a longer half-life at pH 7.4compared to a corresponding protein without the non-native cysteines. Insome embodiments, the stabilized protein has a longer half-life at pH4.6 compared to a corresponding protein without the non-nativecysteines.

As used herein “ex vivo gene therapy” refers to methods where patientcells are genetically modified outside the subject, for example toexpress a therapeutic gene. Cells with the new genetic information arethen returned to the subject from whom they were derived.

As used herein “in vivo gene therapy” refers to methods where a vectorcarrying the therapeutic gene(s) is directly administered to thesubject.

As used herein “fusion protein” and “therapeutic fusion protein” areused interchangeably herein and refer to a therapeutic protein having atleast one additional protein, peptide, or polypeptide, linked to it. Insome instances, fusion proteins are a single protein molecule containingtwo or more proteins or fragments thereof, covalently linked via peptidebond within their respective peptide chains, without chemical linkers.In some embodiments, the fusion protein comprises a therapeutic proteinand a signal peptide, a peptide that increases endocytosis of the fusionprotein, or both. In some embodiments, the peptide that increasesendocytosis is a peptide that binds CI-MPR.

As used herein “plasmid” refers to circular, double-stranded unit of DNAthat replicates within a cell independently of the chromosomal DNA.

As used herein “promoter” refers to a site on DNA to which the enzymeRNA polymerase binds and initiates the transcription of DNA into RNA.

As used herein “somatic therapy” refers to methods where themanipulation of gene expression in cells that will be corrective to thepatient but not inherited by the next generation. Somatic cells includeall the non-reproductive cells in the human body

As used herein “somatic cells” refers to all body cells except thereproductive cells.

As used herein “tropism” refers to preference of a vector, such as avirus for a certain cell or tissue type. Various factors determine theability of a vector to infect a particular cell. Viruses, for example,must bind to specific cell surface receptors to enter a cell. Virusesare typically unable to infect a cell if it does not express thenecessary receptors.

As used herein “vector”, or “gene therapy vector”, used interchangeablyherein, refers to gene therapy delivery vehicles, or carriers, thatdeliver therapeutic genes to cells. A gene therapy vector is any vectorsuitable for use in gene therapy, e.g., any vector suitable for thetherapeutic delivery of nucleic acid polymers (encoding a polypeptide ora variant thereof) into target cells (e.g., sensory neurons) of apatient. In some embodiments, the gene therapy vector delivers thenucleic acid encoding a therapeutic protein or therapeutic fusionprotein to a cell where the therapeutic protein or fusion is expressedand secreted from the cell. The vector may be of any type, for exampleit may be a plasmid vector or a minicircle DNA. Typically, the vector isa viral vector. These include both genetically disabled viruses such asadenovirus and nonviral vectors such as liposomes. The viral vector mayfor example be derived from an adeno-associated virus (AAV), aretrovirus, a lentivirus, a herpes simplex virus, or an adenovirus. AAVderived vectors. The vector may comprise an AAV genome or a derivativethereof.

“Construct” as used herein refers to a nucleic acid molecule or sequencethat encodes a therapeutic protein or fusion protein and optionallycomprises additional sequences such as a translation initiation sequenceor IRES sequence.

The term “transduction” is used to refer to the administration/deliveryof the nucleic acid encoding the therapeutic protein to a target celleither in vivo or in vitro, via a replication-deficient rAAV of thedisclosure resulting in expression of a functional polypeptide by therecipient cell. Transduction of cells with a gene therapy vector such asa rAAV of the disclosure results in sustained expression of polypeptideor RNA encoded by the rAAV. The present disclosure thus provides methodsof administering/delivering to a subject a gene therapy vector such asan rAAV encoding a therapeutic protein by an intrathecal, intraretinal,intraocular, intravitreous, intracerebroventricular, intraparechymal, orintravenous route, or any combination thereof “Intrathecal” deliveryrefers to delivery into the space under the arachnoid membrane of thebrain or spinal cord. In some embodiments, intrathecal administration isvia intracisternal administration.

The terms “recipient”, “individual”, “subject”, “host”, and “patient”,are used interchangeably herein and in some cases, refer to anymammalian subject for whom diagnosis, treatment, or therapy is desired,particularly humans. “Mammal” for purposes of treatment refers to anyanimal classified as a mammal, including humans, domestic and farmanimals, and laboratory, zoo, sports, or pet animals, such as dogs,horses, cats, cows, sheep, goats, pigs, mice, rats, rabbits, guineapigs, monkeys etc. In some embodiments, the mammal is human.

As used herein, the terms “treatment,” “treating,” “ameliorating asymptom,” and the like, in some cases, refer to administering an agent,or carrying out a procedure, for the purposes of obtaining a therapeuticeffect, including inhibiting, attenuating, reducing, pre venting oraltering at least one aspect or marker of a disorder, in a statisticallysignificant manner or in a clinically significant manner. The term“ameliorate” or “treat” does not state or imply a cure for theunderlying condition “Treatment,” or “to ameliorate” (and like) as usedherein, may include treating a mammal, particularly in a human, andincludes: (a) preventing the disorder or a symptom of a disorder fromoccurring in a subject which may be predisposed to the disorder but hasnot yet been diagnosed as having it (e.g., including disorders that maybe associated with or caused by a primary disorder; (b) inhibiting thedisorder, i.e., arresting its development; (c) relieving the disorder,i.e., causing regression of the disorder; and (d) improving at least onesymptom of the disorder. Treating may refer to any indicia of success inthe treatment or amelioration or prevention of a disorder, including anyobjective or subjective parameter such as abatement; remission;diminishing of symptoms or making the disorder condition more tolerableto the patient; slowing in the rate of degeneration or decline; ormaking the final point of degeneration less debilitating. The treatmentor amelioration of symptoms is based on one or more objective orsubjective parameters; including the results of an examination by aphysician. Accordingly, the term “treating” includes the administrationof the compounds or agents of the present invention to prevent or delay,to alleviate, or to arrest or inhibit development of the symptoms orconditions associated with the disorder. The term “therapeutic effect”refers to the reduction, elimination, or prevention of the disorder,symptoms of the disorder, or side effects of the disorder in thesubject.

The term “affinity” refers to the strength of binding between a moleculeand its binding partner or receptor.

As used herein, the phrase “high affinity” refers to, for example, atherapeutic fusion containing such a peptide that binds CI-MPR which hasan affinity to CI-MPR that is about 100 to 1,000 times or 500 to 1,000times higher than that of the therapeutic protein without the peptide.In some embodiments, the affinity is at least 100, at least 500, or atleast 1000 times higher than without the peptide. For example, where thetherapeutic protein and CI-MPR are combined in relatively equalconcentration, the peptide of high affinity will bind to the availableCI-MPR so as to shift the equilibrium toward high concentration of theresulting complex.

“Secretion” as used herein refers to the release of a protein from acell into, for example, the bloodstream to be carried to a tissue ofinterest or a site of action of the therapeutic protein. When a genetherapy product is secreted into the interstitial space of an organ,secretion can allow for cross-correction of neighboring cells.

“Delivery” as used herein means drug delivery. In some embodiments, theprocess of delivery means transporting a drug substance (e.g.,therapeutic protein or fusion protein produced from a gene therapyvector) from outside of a cell (e.g., blood, tissue, or interstitialspace) into a target cell for therapeutic activity of the drugsubstance.

“Engineering” or “protein engineering” as used here in refers to themanipulation of the structures of a protein by providing appropriate anucleic acid sequence that encodes for the protein as to produce desiredproperties, or the synthesis of the protein with particular structures.

A “therapeutically effective amount” in some cases means the amountthat, when administered to a subject for treating a disease, issufficient to effect treatment for that disease.

As used herein, the term “about” a number refers to a range spanningthat from 10% less than that number through 10% more than that number,and including values within the range such as the number itself.

As used herein, the term “comprising” an element or elements of a claimrefers to those elements but does not preclude the inclusion of anadditional element or elements.

EXAMPLES

The following examples are given for the purpose of illustrating variousembodiments of the invention and are not meant to limit the presentinvention in any fashion. The present examples, along with the methodsdescribed herein are presently representative of preferred embodiments,are exemplary, and are not intended as limitations on the scope of theinvention. Changes therein and other uses which are encompassed withinthe spirit of the invention as defined by the scope of the claims willoccur to those skilled in the art.

Example 1: Identifying Amino Acid Residues for Cysteine Substitution ofWild Type α-GAL

The crystal structure of dimerized α-GAL (PDB ID 3HG3) was examined forpotential sites for substituting in cysteine residues, generatingadditional disulfide bonds for enhanced stability (FIG. 1A). NAMD withCHARMM forcefields was used for the analysis. Based on the analysis, thecysteine mutants shown in Table 8 were prepared using standard methodsof directed mutagenesis.

TABLE 8 α-GAL Disulfide Mutants Mutations SEQ ID NO R49C-G361C 2R49C-G360C 3 M51C-G360C 4 D233C-I359C 5 S276C 6

See also FIG. 1B. Amino acid sequences are provided in Table 1.

Example 2: Dimerization and Enzymatic Activity of Modified α-GAL

The formation of disulfide bonded dimers of modified α-GAL was examinedin cell lysate and culture media (FIG. 2A). Clones of each α-GALconstruct were transiently expressed in 293HEK cell. Cell lysates andculture media were run on 4-12% gradient SDS-PAGE and transferred tonitrocellulose. α-GAL was detected by Western Blotting with rabbitmonoclonal anti-α-GAL 1:2000 (abeam ab168341).

Reduced and non-reduced samples were subjected to electrophoresis andWestern blotting. As seen in FIG. 2, M51C-G360C and D233C-I359C versionsof the α-GAL readily formed disulfide bonded α-GAL dimers.

To prepare the samples, 1×10{circumflex over ( )}6 cells were harvestedwith transient expression of α-GAL constructs. Cells were lysed in 500ul 20 mM sodium phosphate buffer pH6.5, 0.25% TX-100. Cell lysate wascentrifuged for 2 min @ 10,000 g and transfer supernatant to new tube.40 ul of cell lysate or culture media was transferred to new tube and 16μl of LDS 4× Sample Buffer was added with 6 μl of 10× Reducing agent(for reducing conditions). Sample mix prepared as below was heated at95° C. for 5 minutes. 1× MOPS SDS running buffer was used forelectrophoresis.

To test for enzymatic activity, lysate or culture medium were incubatedwith 4-methylumbelliferone-α-D-galactopyranoside (4-MUG) substrate for 1hour. Enzymatic reaction was then stopped, and the α-GAL enzymaticactivity was measured by fluorescence at excitation 360 nm and emissionat 450 nm. As shown in FIG. 2B, the M51C-G360C and D233C-I359C disulfideα-GAL mutants were both enzymatically active. Because the specificactivity and amount of α-GAL in each sample were not quantified, FIG. 2Bdoes not provide a quantitative comparison of the activity between thewild type and mutant versions of α-GAL.

Example 3: Stability Analysis of Modified α-GAL in Acidic EnvironmentsOver Time

To test pH stability over 24 h, transiently expressed mutant andwildtype α-GAL was captured using Concanavalin A (ConA) agarosepull-down according to standard methods. The ConA eluate was diluted ineither pH 4.6 buffer or pH 7.4 buffer. Samples were pre-incubated at pH4.6 or 7.4 at 0, 0.5, 1, 2, 4, 5 and 24 hours.

To measure enzyme activity pH 4.6 buffer was added to each sample andtested for activity on a 4-MUG substrate. The reaction mixture wasincubated 37° C. for 1 hour. The reaction was terminated by adding 125uL Stop buffer (0.4 M Glycin-NaOH, pH 10.8) Fluorescence was read withSpectramax plate reader: Ex: 360 nm, Em: 450 nm. The results are shownin FIG. 3A.

For long-term stability testing, transiently expressed modified and wildtype α-GALs were isolated from culture media and enriched and purifiedusing ConA agarose beads as described above. The eluted α-GAL wasincubated in pH 4.6 or pH 7.4 for time course stability experiments. Thetime points included 0 hr, 0.5 hr, 1 hr, 2 hr, 4 hr, 5 hr, 24 hr, 2days, 5 days, 6 days, and 7 days. FIG. 3B shows M51C-G360C α-GAL to bemore stable over a span of 7 days than the wild type control at pH 4.6.Both modified α-GALs were substantially more stable than wild typecontrol at pH 7.4 over 7 days.

Example 4: α-GAL Uptake and Enzymatic Assay by Fabry Patient FibroblastsCell Uptake Protocol

To conduct the uptake assay, on day 1 300,000 Fabry patient fibroblasts(R301Q) were seeded per well in 6-well plates. On day 2, medium wasreplaced with 1.8 mL uptake medium and incubated for 1 hour at 37 C with5% CO2. Cells were given a 200 uL dose of 250 nM enzyme (Fabrazyme,M51C-G360C, D233C-I359C and WT) prepared in uptake medium into 6-wellprepared in step 2 for 16-18 hours. On day 3, 300 uL of 1 M Tris wasadded and incubated at room temperature for 30 min. 400 uL 1M NaH2SO4was added and mixed. Cell plates were washed with 1 ml DPBS two times.500 uL water was added into each well and cells were collected from theplate. Matric-green was added before freezing at −80° C. freezer untilassay. Plates were spun before enzyme and protein assays.

The protein assay was conducted by adding 20 uL cell lysate into 130 uLwater. 150 uL BCA working reagent was added and incubated at 37 C° for 2hours. The plate was then read on a Spectramax.

The enzyme assay was conducted by adding 5 uL cell lysate into 15 uLAssay Buffer then adding 50 uL 4-MUG substrate. This was incubated at37° C. for 1 hour. 125 uL Stop Buffer was added and read at theSpectramax.

As a control, frozen cell lysates were thawed at room temperature andsonicated for 5 min. 50 μL was transferred into 13 mL silanized glasstubes. 25 μL of Glucopsychosine (IS) (conc. 125 ng/mL) was added. 1 mLof methanol was added and the mixture was sonicated for approximately 10min. 500 μL of 1N HCl was added, vortexed then sonicated forapproximately 10 minutes. The mixture was then shaken for approximately30 minutes at room temperature. Samples were centrifuged at 4,000 rpmfor 10 min. at room temperature. Supernatant was transferred ontopreconditioned SPE cartridges.

Solid samples were prepared by condition the SPE cartridges with 1 ml ofmethanol and 1 ml of Millipore water. Samples were loaded on the SPEcartridges. Cartridges were washed with 2 mL 0.1N HCl and then 2 mLMEOH. Samples were eluted with 2 mL 5% ammonium hydroxide in methanolinto clean silanized glass. Samples were evaporated under nitrogen todryness at 40° C. 25 μL of DMSO was added to each extract and vortexed.125 μL (175 μL was used for run 03) of mobile phase B was added andvortexed. Samples were transferred into glass vials. 10 μl was injectedonto analytical column.

Fibroblasts from Fabry disease patients were cultured and seeded in6-well plates. Cells treated with wild type α-GALs were used as positivecontrol for the uptake and subsequent enzymatic studies. Fibroblastswere incubated for 16 to 18 hr with wild type α-GAL, M51C-G360C α-GAL,or D233C-I359C α-GAL. The cells were then lysed for α-GAL enzymaticassay as determined by fluorescent output. FIG. 4A shows that bothM51C-G360C and D233C-I359C α-GALs were able to restore α-GAL enzymaticactivity at least as well wild type α-GAL. See FIG. 4B.Globotriaosylsphingosine (lyso-Gb3) is a biomarker for Fabry Disease.Successful treatment of Fabry Disease leads to significant reduction oflyso-Gb3 as determined by LC-MS/MS.

Example 5: Variant Homodimers Uptake in FB-14 (R301Q) Fabry PatientFibroblasts

Fabry patient fibroblast cells were seeded in 6-well plate for Fabrazymeand α-GAL cell uptake studies. Cells were incubated for 16 h at 37 C, 5%CO2 incubator in uptake media containing 7 nM of either Fabrazyme, wildtype α-GAL, M51C-G360C α-GAL, or D233C-I359C α-GAL. At day 1 cells werewashed and further maintained in regular growth media for 5 additionaldays. Cells were harvested at time points indicated in FIG. 5. Celllysates were used to determine enzyme activity. α-GAL enzyme activitywas determined and normalized with cell lysate protein concentration asnmol/mg protein/hr. It was determined that the variant homodimers have2-3-fold longer half-life inside the cell after cell uptake thanwildtype and 3-4-fold longer than Fabrazyme (FIG. 5).

Example 6: Fabry Disease Gene Therapy in Mouse Model

The AAV vectors were diluted in sterile PBS. The AAV vectors included:AAVhu68.CB7.hGLAnatural.rBG, AAVhu68.CB7.hGLAco.rBG, andAAVhu68.CB7.hGLA-M51C-G360Cco.rBG.

Vector Production

The reference GLA sequence and the variant with the methionine tocysteine at position 51 and glycine to cysteine at position 360 wereback-translated and the nucleotide sequence was codon optimized togenerate a cis-plasmid for AAV production with the expression cassetteunder CB7 promoter. In addition, natural hGLA (reference sequence) cDNAwas ordered and cloned into the same AAV-cis backbone to compare with acodon-optimized sequence. AAVhu68 vectors were produced and titrated aspreviously described (Lock, Alvira et al. 2010, “Rapid, simple, andversatile manufacturing of recombinant adeno-associated viral vectors atscale.” Hum Gene Ther 21(10): 1259-1271). Briefly, HEK293 cells weretriple-transfected and the culture supernatant was harvested,concentrated, and purified with an iodixanol gradient. The purifiedvectors were titrated with droplet digital PCR using primers targetingthe rabbit Beta-globin polyA sequence as previously described (Lock M,R. Alvira, S. J. Chen and J. M. Wilson, “Absolute determination ofsingle-stranded and self-complementary adeno-associated viral vectorgenome titers by droplet digital PCR.” Hum Gene Ther Methods 25(2):115-125 (2014)).

Animals

Mus musculus, Fabry mice Gla knock-out, in a C57BL/6/129 backgroundfounders were purchased at Jackson Labs (stock #003535—“also known as”α-Gal A KO mice”). The breeding colony was maintained at the GeneTherapy Program AAALAC accredited barrier mouse facility, usingheterozygote to heterozygote mating in order to produce null and WTcontrols within the same litters. The Gla knock-out mouse is a widelyused model for Fabry disease.

The mice appear clinically normal, but they exhibit a progressiveaccumulation of the GLA substrate Globotriaosylsphingosine (akalyso-GB3) in plasma and Globotriaosylceramide (aka GL3, GB3) in liver,heart, kidney, skin small and large intestine and the central nervoussystem. The small size, reproducible phenotype, and efficient breedingallow quick studies that are optimal for preclinical candidates in vivoscreening.

Animal holding rooms were maintained at a temperature range of 64-79° F.(18-26° C.) with a humidity range of 30-70%. Animals were housed withtheir parents and littermates until weaning and next in standard cagingof 2 to 5 animals per cage in the Translational Research Laboratories(TRL) GTP vivarium. Cages, water bottles, and bedding substrates areautoclaved into the barrier facility. An automatically controlled12-hour light/dark cycle was maintained. Each dark period began at 1900hours (±30 minutes). Food was provided ad libitum (Purina, LabDiet®,5053, Irradiated, PicoLab®, Rodent Diet 20, 251b). Water was accessibleto all animals ad libitum via individually placed water bottle in eachhousing cage.

In Vivo Studies and Histology

Mice received 5×10¹¹ GCs (approximately 2.5×10³ GC/kg) ofAAVhu68.CB7.hGLA (various hGLA constructs) in 0.1 mL via the lateraltail vein, were bled on Day 7 and Day 21 post vector dosing for serumisolation and were terminally bled (for plasma isolation) and euthanizedby exsanguination 28 days post injection. Tissues were promptlycollected, starting with brain.

Tissues for histology were formalin-fixed and paraffin embedded usingstandard methods. Spinal cord with DRG (in bone) was fixed in ZF,decalcified in EDTA and processed according to standard procedures ofthe GTP Morphology Core. Zinc-formalin is used to obtain good tissuepreservation and was used to stain the Gb3 storage by IHC and formorphology (H&E).

Immunostaining for GL3 was performed on formalin-fixed paraffin-embeddedsamples. Sections were deparaffinized, blocked with 1% donkey serum inPBS+0.2% Triton for 15 min, and then sequentially incubated with primary(Amsbio AMS.A2506, anti-Gb3 monoclonal antibody) and biotinylatedsecondary antibodies diluted in blocking buffer; an HRP basedcolorimetric reaction was used to detect the signal. Slides werereviewed in a blinded fashion by a board-certified VeterinaryPathologist.

Fabry −/− mice vehicle PBS controls display marked GL3 (dark staining onIHC stained sections) accumulation. WT mice and all vector treated micehave near complete to complete clearance of GL3 storage (FIG. 6).

GLA Activity

Plasma or supernatant of homogenized tissues were mixed with 6 mM4-MU-α-galactopyranoside pH 4.6, 90 mM GalNAc and incubated for threehours at 37° C. The reaction was stopped with 0.4 M glycine pH 10.8.Relative fluorescence units, RFUs were measured using a Victor3fluorimeter, ex 355 nm and emission at 460 nm. Activity in units ofnmol/mL/hr was calculated by interpolation from a standard curve of4-MU. Activity levels in individual tissue samples were normalized fortotal protein content in the homogenate supernatant. Equal volumes areused for plasma samples.

Fabry −/− mice displayed a complete lack of α-Gal A activity. Treatmentof Fabry mice with AAVhu68.CB7.hGLA-M51C-G360Cco.rBG GTx vector resultedin >7-fold higher GLA activity in kidney than wildtype (FIG. 7).

Quantitation of Globotriaosylceramide (aka GL3, GB3) by LC-MS/MS

The GLA substrate, GL3, in tissue homogenate was quantified by aLC-MS/MS assay. Briefly, an internal standard was added to homogenatesamples (50 μL) and the samples were processed using C18-basedsolid-phase extraction (SPE). A standard curve was prepared to knownconcentrations of GL3 (8.83 nM to 4.41 μM) from stocks containing twelveceramide forms. Monitored responses from all twelve isoforms were to besummed and a ratio was generated with respect to internal standard inthis assay. The resultant ratios of study samples were then comparedagainst the prepared curve for GL3 quantification.

Fabry −/− mice displayed a >10-fold accumulation of the GLA substrateGlobotriaosylceramide (GL3). Treatment of Fabry mice withAAVhu68.CB7.hGLA-M51C-G360Cco.rBG GTx vector resulted in a completedreduction of GL3 in kidney to wildtype level (FIG. 8).

Quantitation of Globotriaosylsphingosine (aka lyso-GB3) by LC-MS/MS

The GLA substrate, lyso-GB3, in plasma is quantified by a LC-MS/MSassay. Briefly, a stable C13-labeled internal standard is added to theplasma samples (50 μL) and the samples are processed using C18/cationexchange mixed mode solid-phase extraction (SPE). A standard curve isprepared to known concentrations of lyso-GB3 (0.254 nM to 254 nM) andlyso-GB3 response of study samples are then compared against theprepared curve for lyso-GB3 quantification.

GLA Signature Peptide by LC/MS

Plasma is precipitated in 100% methanol and centrifuged. Supernatantsare discarded. The pellet is spiked with a stable isotope-labeledpeptide unique to hGLA as an internal standard and resuspended withtrypsin and incubated at 37° C. for two hours. The digestion is stoppedwith 10% formic acid. Peptides are separated by C-18 reverse phasechromatography and identified and quantified by ESI-mass spectroscopy.The total GLA concentration in plasma is calculated from the signaturepeptide concentration.

Cell Surface Receptor Binding Assay

A 96-well plate is coated with receptor, washed, and blocked with BSA.CHO culture conditioned media or plasma containing equal activities ofeither rhGLA or engineered GLA is serially diluted three-fold to give aseries of nine decreasing concentrations and incubated with co-coupledreceptor. After incubation the plate is washed to remove any unbound GLAand 4-MU-α-galactopyranoside added for one hour at 37° C. The reactionis stopped with 1.0 M glycine, pH 10.5 and RFUs were read by aSpectramax fluorimeter; ex 370, emission 460. RFU's for each sample andare converted to activity in nmol/mL/hr by interpolation from a standardcurve of 4-MU. Nonlinear regression is done using GraphPad Prism.

Example 7: Stabilized PPT-1 Constructs

A stabilized PPT-1 construct was engineered based on the crystalstructure (PDB ID 3GRO). These two cysteines are predicted to form adisulfide bond, which stabilizes the structure and was found to extendthe half-life of enzymatic function (see data below). The expressionlevel of this construct in HEG 293 was found to be close to that ofwildtype PPT-1.

Improved Stability and Half-Life of PPT-1 Enzyme

An intramolecular disulfide bridge was engineered into PPT-1 in order tostabilize the enzyme, as determined by measuring the half-life of theactive enzyme. The residues that were mutated, A171C/A183C, were chosenbecause the equivalent residues in a homologous protein, PPT-2, form adisulfide bridge. This natural variation in a homologous protein wasused to inform the engineering efforts in PPT-1.

Stability Testing of Construct PPT-1

Construct PPT-1 was expressed transiently in HEK 293T cells and theconditioned media was harvested five days post-transfection. The samewas done for wildtype PPT1. Enzyme activity assays were performed onboth sets of conditioned media over a course of 48 or 72 hours. Theamount of enzymatic activity retained over time was determined in orderto compare the cysteine double mutant with WT. (FIG. 9).

Half-life was estimated in two ways representing the alpha and betaphases, as activity appears to be a biphasic elimination (see log plotadjacent to the PK table below). The alpha half-life was estimatedduring the early terminal or distribution phase, the beta half-life wasestimated during the terminal elimination phase. For ATB200 total GAAprotein analyses, the alpha phase is often reported as it is moremeaningful for demonstrating effect of AT2221 on binding andstabilization of ATB200 while in blood, during distribution intotissues.

Pharmacokinetics of Construct PPT-1, including C₀ and AUCs, arereported. The AUCiiity was derived from the same elimination rateconstant used to estimate the beta half-life.

TABLE 9 PPT-1 Pharmacokinetics (5 day average) Construct C₀ AUC_(0-t)AUC_(0-∞) t_(1/2α) t_(1/2β) Wildtype 1.46 15.9 21.0 1.7 23.1 Cys-mutant3.40 65.6 80.3 2.8 28.2

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments described herein may beemployed. It is intended that the following claims define the scope ofthe invention and that methods and structures within the scope of theseclaims and their equivalents be covered thereby.

What is claimed is:
 1. A gene therapy vector comprising a nucleic acid construct comprising: a nucleic acid encoding a stabilized form of a protein for treating a genetic disorder, the stabilized form comprising one or more non-native cysteine residues that form a disulfide bridge between non-native cysteines within the protein or between non-native cysteines of two monomers of the protein.
 2. The gene therapy vector of claim 1, wherein the protein is selected from the group consisting of alpha-galactosidase A, β-glucocerebrosidase, glucocerebrosidase, lysosomal acid lipase, glycosaminoglycan alpha-L-iduronidase, alpha-L-iduronidase, N-sulfoglucosamine sulfohydrolase (SGSH), N-acetyl-alpha-glucosaminidase (NAGLU), iduronate-2-sulfatase, N-acetylgalactosamine-6-sulfatase, glycosaminoglycan N-acetylgalactosamine 4-sulfatase, alpha-glucosidase, tripeptidyl peptidase 1 (TPP1), palmitoyl protein thioesterases (PPTs), ceroid lipofuscinoses neuronal 4, ceroid lipofuscinoses neuronal 10 (cathepsin D), ceroid lipofuscinoses neuronal 11 (progranulin), ceroid lipofuscinoses neuronal 13 (cathepsin F), ceroid lipofuscinoses neuronal 14 (KCTD7), ceroid lipofuscinoses neuronal 15 (TBCK), and cyclin dependent kinase like
 5. 3. The gene therapy vector of claim 1, where the stabilized protein comprises a lysosomal enzyme.
 4. The gene therapy vector of claim 1, wherein the stabilized protein comprises a stabilized α-galactosidase (α-GAL) protein or a stabilized palmitoyl protein thioesterase 1 (PPT1).
 5. The gene therapy vector of claim 4, wherein the stabilized α-galactosidase A (α-GAL) protein comprises one or more non-native cysteine residues selected from the group consisting of: (i) D233C and I359C; and (ii) M51C and G360C.
 6. The gene therapy vector of claim 4, wherein the stabilized PPT1 protein comprises non-native cysteine residues A171C and A183C.
 7. The gene therapy vector of claim 1, wherein the stabilized protein has a longer half-life at pH 7.4 compared to a corresponding protein without the non-native cysteines.
 8. The gene therapy vector of claim 1, wherein the stabilized protein can replace a protein that is defective or deficient in the genetic disorder.
 9. The gene therapy vector of claim 1, wherein the stabilized protein can reduce or slow one or more symptoms associated with the genetic disorder.
 10. The gene therapy vector of claim 1, wherein the stabilized protein is more effective at reducing or slowing one or more symptoms of the genetic disorder, compared to an unstabilized protein.
 11. The gene therapy vector of claim 1, wherein the genetic disorder is a lysosomal storage disorder.
 12. The gene therapy vector of claim 1, wherein the genetic disorder is selected from the group consisting of aspartylglucosaminuria, Batten disease, cystinosis, Fabry disease, Gaucher disease type I, Gaucher disease type II, Gaucher disease type III, Pompe disease, Tay Sachs disease, Sandhoff disease, metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis type II, mucolipidosis type III, mucolipidosis type IV, Hurler disease, Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B, Sanfilippo disease type C, Sanfilippo disease type D, Morquio disease type A, Morquio disease type B, Maroteau-Lamy disease, Sly disease, Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pick disease type C1, Niemann-Pick disease type C2, Schindler disease type I, Schindler disease type II, adenosine deaminase severe combined immunodeficiency (ADA-SCID), chronic granulomatous disease (CGD), infantile, juvenile and adult forms of neuronal ceroid lipofuscinosis, and CDKL5 deficiency disease.
 13. The gene therapy vector of claim 1, wherein the gene therapy vector is a viral vector selected from the group consisting of an adenovirus vector, an adeno-associated virus vector, a retrovirus vector, a lentivirus vector, and a herpes virus vector.
 14. The gene therapy vector of claim 1, wherein the nucleic acid construct is comprised in a viral vector genome.
 15. The gene therapy vector of claim 14, wherein the viral vector genome comprises a recombinant AAV (rAAV) genome.
 16. The gene therapy vector of claim 15, wherein the rAAV genome comprises a self-complementary genome or a single-stranded genome.
 17. The gene therapy vector of claim 15, wherein the rAAV genome comprises a first inverted terminal repeat and a second inverted terminal repeat.
 18. The gene therapy vector of claim 15, wherein the rAAV genome further comprises an SV40 intron and/or a poly-adenylation sequence.
 19. The gene therapy vector of claim 1, wherein the construct comprises a nucleic acid sequence encoding an α-GAL protein, wherein the nucleic acid sequence is at least 85% identical to one of SEQ ID NOs: 7-12.
 20. The gene therapy vector of claim 1, wherein the construct comprises a nucleic acid sequence encoding a PPT1 protein, wherein the nucleic acid sequence is at least 85% identical to one of SEQ ID NO: 15-16.
 21. The gene therapy vector of claim 1, wherein the construct further comprises a promoter sequence.
 22. The gene therapy vector of claim 21, wherein the promoter is a constitutive promoter or a tissue-specific promoter.
 23. The gene therapy vector of claim 1, wherein the construct further comprises one or more nucleic acid sequences selected from the group consisting of: a Kozak sequence, a CrPV IRES, a nucleic acid sequence encoding a linker, a nucleic acid sequence encoding a signal sequence, and a nucleic acid sequence encoding an IGF2 peptide.
 24. A pharmaceutical composition comprising the gene therapy vector of claim 1 and a pharmaceutically acceptable excipient, carrier, or diluent.
 25. The pharmaceutical composition of claim 24, wherein the excipient is selected from the group consisting of saline, maleic acid, tartaric acid, lactic acid, citric acid, acetic acid, sodium bicarbonate, sodium phosphate, histidine, glycine, sodium chloride, potassium chloride, calcium chloride, zinc chloride, water, dextrose, N-methylpyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, ethanol, propylene glycol, polyethylene glycol, diethylene glycol monoethyl ether, and surfactant polyoxyethylene-sorbitan monooleate.
 26. A method for treating a genetic disorder in a subject comprising administering to the subject a therapeutically effective amount of the gene therapy vector of claim
 1. 27. The method of claim 26, wherein the gene therapy vector or pharmaceutical composition is delivered by intrathecal, intracerebroventricular, intraperenchymal, or intravenous injection, or a combination thereof.
 28. The method of claim 26, wherein the gene therapy vector or pharmaceutical composition reduces or slows one or more symptoms of the genetic disorder in the subject.
 29. The method of claim 26, wherein the genetic disorder is a lysosomal storage disorder.
 30. The method of claim 26, wherein the genetic disorder is selected from the group consisting of aspartylglucosaminuria, batten disease, cystinosis, Fabry disease, Gaucher disease type I, Gaucher disease type II, Gaucher disease type III, Pompe disease, Tay Sachs disease, Sandhoff disease, metachomatic leukodystrophy, mucolipidosis type I, mucolipidosis type II, mucolipidosis type III, mucolipidosis type IV, Hurler disease, Hunter disease, Sanfilippo disease type A, Sanfilippo disease type B, Sanfilippo disease type C, Sanfilippo disease type D, Morquio disease type A, Morquio disease type B, Maroteau-Lamy disease, Sly disease, Niemann-Pick disease type A, Niemann-Pick disease type B, Niemann-Pick disease type C1, Niemann-Pick disease type C2, Schindler disease type I, Schindler disease type II, adenosine deaminase severe combined immunodeficiency (ADA-SCID), chronic granulomatous disease (CGD), neuronal ceroid lipofuscinosis, and CDKL5 deficiency disorder. 